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Why Correct Wheel Alignment Is Essential

As the number of vehicles on the road increases, it becomes even more important for those owning a vehicle to ensure that it is being properly maintained. Needless to say, wheels play a crucial role in keeping both vehicles and passengers safe on the road.

For this reason, Parma Group stresses the need to thoroughly examine the wheels before the vehicle is taken out for a drive on the road. Wheel safety is something that every business should take seriously, especially those who heavily rely on fleets to get the work done.

In this article, we take you through the importance of aligning the wheels in order to ensure greater safety of automobiles.

The Dangers of Misaligned Wheels

When the wheels of a vehicle are misaligned, there are many risks that a vehicle is exposed to. Following are some of the dangers of driving a vehicle with misaligned wheels:

The alignment of wheels has a direct impact on the ability of a driver to steer the vehicle.

When the driver lets go of the steering wheel, a vehicle with misaligned wheels may naturally pull or drift to one side of the road.

Misaligned wheels subject the tread to a constant drag and as a result, they get worn out unevenly and prematurely. While in certain applications the tread life is sacrificed to achieve the desired performance or stability.

Due to uneven tear, tyres lose their grip over the road’s surface rapidly.

Vehicles with a greater drag tend to consume more fuel than those vehicles which have perfectly aligned wheels.

Misaligned wheels compromise the driver’s ability to turn around corners and also affect the braking system of the vehicle.

Wheel Alignment

When the rotation of wheels is in line with the direction of travel, the wheel is said to be aligned. The process by which a misaligned wheel is made to rotate in a straight line is known as wheel alignment. When the calibration of a wheel is right, it becomes easier to steer the vehicle.

The factors that can affect wheel alignment are as follows:

    1. Poor road conditions.
    2. Wheels getting accidentally hit by objects such as parking blocks and curbs.
    3. Miscalculations which bring the vehicle in close contact with road dividers.
    4. Improper alignment at the hands of a non-professional.

A misaligned wheel can be easily identified as its orientation on the vehicle will be slightly off the centre. It may not be clearly visible to the naked eye, but the person sitting behind the steering wheel may find it difficult to steer the vehicle in the desired direction.

Following are the three major considerations that need to be taken into account when aligning the wheels:

  • Camber
  • Caster
  • Toe

Automobile manufacturers usually specify the alignment angles that give the vehicle its handling characteristic. These angles can also be adjusted according to the purpose which the vehicle is expected to serve.

For example, vehicles that are used in motorsports need a specific handling and as a result its alignment angles will differ greatly from those vehicles that are driven on ordinary roads for non-racing purposes. The alignment angles are also different for vehicles that are used for off-roading purposes.

The important alignment angles of camber, caster and toe have been explained in detail below:


The alignment of a wheel must be perfectly perpendicular to the surface. The deviation from the perpendicular in degrees is known as the camber angle. A perfectly aligned wheel has a camber angle of 0 degrees.

A negative camber implies that the wheel tilts inwards with respect to the perpendicular. This brings the wheel closer to the fender walls and as a consequence, the wheel experiences uneven wear and tear. A positive camber on the other hand means that the wheel tilts away from the vehicle.


When looking down at our feet, we can either make the toes point inward or outward. Applying the similar logic to wheels, when the top view of a vehicle is considered, the wheels can either face inward towards each other or outwards away from each other.

When the wheels are not perfectly aligned, their alignment angle doesn’t run parallel to the centre line of the vehicle. Positive toe is an alignment wherein the tyres face each other. Negative toe on the other hand implies that the wheels are pointing outwards.

The presence of negative or positive toe causes the edges of the wheels to wear out unevenly. Positive toe reduces the turning ability of a vehicle, whereas negative toe increases the cornering ability of a vehicle.


The displacement in terms of the angle made by the steering axis with respect to the vertical axis of a steered wheel is known as Caster. If it is angled forward, the caster is said to be positive, while if it is angled backward, the caster is said to be negative.

Positive caster offers greater stability to vehicles at higher speeds by increasing the steering effort. Adjustments can be made to the caster and toe to prevent the vehicle from running into the oncoming traffic and drifting away to the right while rolling.

Parma Group stresses the need for regular maintenance of wheels to ensure the wheel assembly and the wheel itself doesn’t pose any threat to the safety of vehicles on the road.

Wheel Assembly Explained

Most vehicles employ an automotive part known as wheel assembly to make the movement of wheels possible. Several components are fitted together in a wheel assembly so that the wheels can achieve the necessary motion and this is all done with wheel safety in mind.

Following are some of the components used in a wheel assembly and their functions:

Types of Wheel

Wheels that are driven by the drive shaft are known as driven wheels, whereas wheels that are not controlled by it are known as undriven wheels. The type of transmission decides whether the front, rear or all wheels of a vehicle will be controlled by the drive shaft. 

Types of Hub

The hubs which are manufactured for driven wheels may have a construction that appears similar to that of hubs designed for undriven wheels. However, the hubs of driven wheels are manufactured in a slightly different way compared to that of undriven wheels. Hubs of driven wheels are different in this aspect in that they need to incorporate drive shafts too.

In the case of a front wheel drive, the hub is responsible for two tasks. The first is to drive the wheels and the other is to swivel. If a hub is unable to perform any of these tasks efficiently there can be difficulties in steering the car.

Hub Carrier

The hub assembly is either placed inside or in connection with a large casting which is known as a hub carrier. By making use of ball joints, the hub carrier is connected to the upper and lower wishbones of the suspension mechanism. It is due to this arrangement that a hub carrier can swivel and also move up and down.

A rear wheel drive that employs the use of MacPherson struts has a slightly different design when it comes to wheel assembly. At the bottom, the hub carrier is in contact with a ball joint while at the top it is either bolted or a part of the strut.

It is the top mount of the strut, which is joined with the inner wing that is responsible for the upper swivel. The steering gear controls the amount of swivel that the hub carrier can manage to bring about. The steering gear and hub carrier is held together by a steering arm and another joint.

Drive Shaft Splines

The transmission of drive from the drive shaft to the hub is made possible by splines grooves which are machined for a few inches along the end of the shaft. It engages with the matching grooves that have been machined inside the hub so that it holds together properly.

Such an arrangement facilitates contact over a large surface area resulting in greater transmission of power. Despite the splines being shallow, a splined joint is a compact way of high power transmission.

Driving the Hub

The movements caused by the steering wheel are passed onto the drive shaft which drives the hub accordingly. The driving shaft makes use of a flexible joint, also known as a constant velocity joint, which is placed at each end to allow for suspension movement and steering swivel.

The drive shaft runs through the centre of hub carrier. At one of its ends, the drive shaft is connected to the rotating part of the hub. As a result, the rotating part of the hub also turns each time the drive shaft turns.


Generally in driven wheels, two ball bearings are used together and two pairs, each consisting of two bearings, are mounted inside the hub carrier. The hub can only be held steady and rotated smoothly if an inner and upper pair of bearings is used.

In undriven wheels, the drive shaft runs through the centre of bearings instead of running through the hub carrier. In this arrangement, the hub doesn’t directly support the wheel as it does in the former assembly. In this type of assembly, the hub is fixed over the protruding end of the shaft and it is the shaft which bears the load of the wheel instead of the hub.

On the outer end of the drive shaft is a nut which holds the hub on to the car and it is present in both types of design. The drive shaft passes through the middle of the hub and runs from the inside while the hub fits from the outside of the hub carrier. The nut is held by a split pin and it is always done up tightly.

Wheel nut caps can also be used to provide security to the wheel assembly. Wheel nut caps help to keep in check, the various forces that act on a wheel which are also responsible for the wheels to come out loose.

Bearing Type

Undriven hubs usually make use of taper roller bearings which are predominantly effective at handling radial forces. In this type of bearing, cones or cylinders are used to separate the movement of different surfaces of a bearing.

Driven hubs on the other hand make use of ball bearings which provide greater flexibility so as to facilitate greater movement within the wheel assembly. In a ball bearing, rollers or metal balls are used which roll against inner and outer surfaces of a bearing.

The bearings are usually separated by some distance and there are two ways they can be installed. They can be held in place by retaining them in threaded rings or by press-fitting them into the hub carrier.

When the central hub nut has been tightened, a tube or spacer should be fitted between the two inner races. This way, bearings which are separated are not subjected to excessive side loads. In these mechanisms, presence of dirt can disrupt the motion of bearings and therefore oil seals must be used to prevent dirt from entering. Regular wheel and tyre maintenance is advised to prevent the various issues that can lead to detachment of wheel from the vehicle.

Parma Group is dedicated to the improvement of road safety and our products have been designed to ensure the safety of the vehicle and those who occupy it.

Contact us today to make your vehicle roadworthy.

Common Causes of Bearing Failures

Vehicles are subjected to a lot during their day-to-day use. Certain parts are constantly exposed to friction and this ultimately leads to their deterioration and breakdown. While there is little one can do to prevent breakdown, there are various measures that can be taken to prevent this costly downtime from becoming a regular occurrence.

In this post, we cover various factors that lead to the failure of bearings and also the steps that can be taken to prevent them from happening frequently. Knowledge of these common problems and their solutions will help you to extend the life of bearings, as well as to reduce the number of times you have to replace them due to their failure.


Lubrication is known to be a leading cause for failure of bearings. It is estimated that improper lubrication accounts for nearly 80% of bearing failures. Some of the common reasons for the degradation of lubricant are as follows:

Usage of inappropriate lubricants.

Wrong temperatures of those surfaces that are in contact with each other or rather experience high amounts of friction can attain very high temperatures and this can lead to the degradation of lubricant.

The amount of lubrication used is less than is actually required.

Signs to look for:

You should look for the presence of discoloured rolling elements, mostly blue or brown in colour or their tracks. If you find the bearing to be overheating or find traces of excess wear and tear on the surface of bearing.

How to Fix:

Make sure you are using the right lubricant and not applying it in excess so as to result in grease loss.

Intervals between subsequent lubrication sessions should be exactly as specified by the manufacturer or technician.


Contamination is said to occur when foreign substances enter the bearing, the lubricant or the cleaning solutions used. Contaminants include dust, dirt, abrasive grit or steel chips that usually find their way into the bearing assembly either through the tools used or dirty hands.

Signs to look for:

Visible dents on the surface of rolling elements.

Movement of bearings result in vibration from the raceways.

How to Fix:

The lubricant should be filtered.

Hands, tools, work areas and fixtures should be cleaned regularly.


The correct method of mounting bearings is to press fit them into the rotating ring.

Signs to look for:

The degradation of bearings can be attributed to several factors such as cracked rings, early fatigue, high operating temperatures and the premature failure of bearings. Most of these problems develop due to the improper mounting of bearings or exerting less pressure on raceways.

Dents can be caused due to the application of excess pressure to the outer race. If the shaft fitting is loose, tiny particles of metal along with heat are produced due to the rotation of the shaft within the inner ring.

Similar damage is caused if the housing fit is loose. Cracked rings, premature failure and high operating temperature are often a result of a tight shaft or housing fit.

How to Fix:

Mounting instructions should be followed carefully and adequate training should be provided to the employees responsible for mounting the bearings. The staff responsible for this task should understand at once whether bearings have not been mounted properly or not.

False Brinelling

If the equipment is idle and the balls move rapidly in the raceway the lubricant wears away. Also, if the bearing does not rotate sufficiently fresh lubricant will not able to get back to the place from where it starts. Both are the most likely possibilities that lead to false brinelling.

Signs to Look for:

If linear wear marks are found in the axial direction along the track of the rolling element, then it is an indication that the bearing has been subjected to false brinelling.

Also, if there are no raised edges on the surface as against those that are a result of improper mounting, then false brinelling is said to have occurred.

How to Fix:

Vibrations that cause the balls to move should be absorbed or eliminated. Lubricants that contain anti-wear additives can prevent this problem.

Other Factors

Besides the reasons listed above, the other factors that can lead to the failure of bearings include corrosion, electrical damage, fatigue, overheating and placement of excess load on the bearings.

By being aware of the factors that lead to the failure of a bearing, one can prevent their deterioration and in this way increase the overall safety of the vehicle.

At Parma Group we are dedicated to making the roads safer. Here you can find products that can make your wheels more secure, meaning your vehicles can operate in exactly the way they should.


Adjusting Wheel Bearings – What You Need To Know

Usually after every 12,000 miles, wheel bearings should be removed and carefully inspected for any inconsistency that could affect the functioning of the wheel. Wheel safety guidelines suggest that wheel bearings should be adjusted after every 12,000 miles and repacked with grease after every 36,000 miles.

Influence of Design

Bearings which are installed on undriven wheels i.e. the rear wheels of front-wheel-drive cars and front wheels of rear-wheel-drive cars are known to have a similar design.

The hub nuts placed on driven wheels, which have their independent suspension, are tightened to a high torque setting. As a result, the bearings which are used on driven wheels require less adjustment than those installed on undriven wheels.

The method of adjusting bearings which are fixed on driven wheels varies from vehicle to vehicle. The bearings which are installed on rear wheels on a live axle are not frequently or easily replaced. It takes a few extra steps compared to the replacement procedure of unitized bearings.

Adjusting Non-Driven Bearings

The bearings which are installed on non-driven wheels should be adjusted in the following two situations:

The hub nut should be tightened, if found to be loose.

The hub nut should be loosened, if found to be too tight.

To carry out the procedure, the wheel must be attached to the car and an axle stand should be used to raise the car so as to provide the right angles required for making adjustments to the bearing.

The bearings cannot be adjusted without removing the wheel trim. In certain vehicles, the wheel may need to be taken out before the trim can be removed. However, before adjusting the bearings, the wheel has to be installed back in its place. The wheels on which no maintenance work is to be performed should be chocked so as to prevent the car from moving.

The wheels on which the handbrakes are applied should be serviced only after releasing the handbrake. The dust cap should be removed carefully using two medium sized screwdrivers. The screwdriver should be placed between the raised flange and the hub’s surface. With a swift inward motion of the screwdriver’s handle, the dust cap can be taken off without causing damage to the hub’s surface or the dust cap.

If a cap has not been removed for a long time or the vehicle’s condition won’t allow for the dust cap to be taken out, it can be hammered off without causing much damage to it. Even if the cap does get damaged, it can be conveniently replaced as they are inexpensive.

The hub nut that you encounter after having taken off the wheel trim and the dust cap decides what your approach should be and which tool you may have to use to carry out the necessary maintenance task.

The hub can be any one of the following types:

A castellated nut i.e. a nut which has notches cut into one of its ends. Each notch or slot is also threaded from the inside. The nut is retained in its position by a split pin.

It can also be a plain nut with a castellated retainer fastened over it and held in its place once again by a split pin.

Another way the hub can be secured is by ‘peening’. In this method, the outer edge of the metal is punched until it spreads over the surface. It acts as a seal on the threaded axle end.

There is also another type which has been used in certain models of VW. It makes use of a nut with a threaded collar which is squeezed tight by a bolt. Wrenches with predefined sockets may not be of much help when unfastening them. However, pliers with adjustable grip over nuts such as self locking wrenches can be used to turn them.


In order to remove the fastened nut, you should use a wrench with a socket that fits the nut well. In case the nut has been held in position by a split pin, you should have a right-sized pin ready for its replacement. The same goes with a peened nut as it too gets damaged in the process of removing it. For a peened nut you must make use of a cold chisel and hammer.

The nut and axle end should have some grease on their surface. If they are found to be dirty, the bearings should be taken out. Using clean grease, the bearing should be repacked in the right quantity.

Traces of metal are a sign of disintegration and the bearing should be replaced at once.

The torque wrench should be correctly calibrated according to the hub nut. The calibration differs depending on the type of vehicle and can range from 11 to 60 lb ft (or 1.5 to 8.3 kg m).

It should be noted that the adjustment should be done strictly according to the service manual provided to you or as advised by a local dealer.

Now the wheel must be turned slowly using one hand, in the forward direction of travel. At this point you should carefully tighten the hub nut in accordance with the torque set on other wheels. It has been done correctly if the wheel is able to rotate smoothly.

When the nut becomes too tight, you may notice that the wheel is dragging or its movement is facing resistance as a result of moving too close to the surface on which it has been mounted.

Adjusting Driven Bearings

High torque settings are generally applied to the hub nuts of driven wheels which are not mounted on live axles. It can range from 150-200 lb ft (or 21-25 kg m). The wheel should be in contact with the ground and it should be under the weight when the final tightening is being carried out. Care must be taken to ensure that the calibration of torque is exactly as per guidelines.

Contact us today to increase the safety of your wheels. Parma Group strive to improve the wheel safety of vehicles on the road and provide all the products to ensure the safe movement of huge fleets involved in business operations

Another wheel loss leads to yet another life lost this time in New York there isn't a need for this to keep happening there are multiple products that prevent wheel loss on commercial vehicles maintenance and wheel safety fitment should be a priority not something that happens if we can be bothered!!

Wheel Safety Guide: Wheel Loss Analysis

Wheel detachment has consistently ranked as one of the major concerns of the transportation industry when it comes to vehicle safety. The risks associated with detachment of wheels from a vehicle justify to quite an extent, the concerns that have been raised over wheel security and the need to come up with effective measures to tackle this age-old problem.

Over the years, manufacturing of automobile equipment has taken several leaps in terms of design and durability of material, each increasing the safety and overall reliability of vehicles. However, despite these advances and the efforts taken to spread awareness regarding the importance of vehicle maintenance, wheel detachment from heavy commercial vehicles remains to be a cause of concern for operators.

Wheel detachment is mostly attributed to problems that develop in the design of equipment due to the extreme wear and tear that they are subjected to during the movement of vehicles. However, proper maintenance can play a significant role in controlling the conditions that can lead to wheel loss.

Although the annual frequency of accidents caused due to wheel loss is comparatively lower to the number of accidents caused due to other reasons, it is an issue that must be addressed to further increase vehicle safety in the UK.

Consequences of Wheel Loss

In most cases, a detached wheel comes to rest without causing damage or harm to the vehicles around. At high speeds however, wheel detachment can cause fatalities. A wheel which has come loose can accelerate to speeds as high as 95 mph and can rise up to heights of 50 metres above the ground. If it collides with a vehicle on its way at those speeds and height, it can exert a force that is equal to 10 tonnes on the colliding surface.


Research was conducted by the Transport Research Laboratory (TRL) that was commissioned by the Department for Transport. Its findings were as follows:

Wheel fixing defects account for nearly 7,500 to 11,000 problems related to wheel fixing

Other problems and their typical annual frequency have been stated below:

Wheel detachments – Between 150 and 400

Damage only Accidents – Between 50 and 134

Injury Accidents – Between 10 and 27

Fatal Accidents – Between 3 and 7

If wheel loss due to faults in equipment is considered, following is the share of each type of equipment failure:

The report also suggested that when components are properly tightened and in good condition, the current designs of wheel fixings are able to provide the required clamp load. The fastening of the wheel components is also caused due to joint relaxation and variations in torque to clamp ratio and component temperature.

The underlying problem is that the design of these components is not yet of the required resistance to put up with the massive amounts of friction that these components undergo. As a result, the components face severe degradation owing to the lack of a maintenance free design. It thereby necessitates careful handling of components.

Reasons for Loosening of Wheel Fixings

The vehicle itself contributes the most to the degradation of wheel fixings by exerting a variety of forces on them. These forces include heat effects, vibration, cornering forces and braking and acceleration.

Even the loosening of one wheel nut can cause the remaining nuts to come loose. With the loosening of several wheel nuts, the overall clamping force decreases. This reduction in clamping force affects the arrangement of wheel, drum and hub, causing them to become detached from each other as clamping force further decreases.

The wheel begins to move with respect to the hub, when the clamping force becomes lesser than the forces on the wheel. This movement causes remaining nuts to come loose and it also results in side loading.

If these problems are not identified in time, they can gradually progress to cause bigger issues such as fretting fatigue cracks, fatigue failure of studs, elongated stud holes and wheel separation.

According to the laboratory test programmes, following is the sequence of events that ultimately lead to wheel loss:

Settlement or deposition within the fixing causes constant friction leading to a reduction in clamping force.

As wear and tear increases, clamping force further reduces.

Some nuts may become ineffective in providing any clamping force whatsoever after they become loose beyond a certain extent.

If the studs lose their hold over the wheel, they might get thrown off it with tremendous velocity. Even if they do not leave the wheel right away, they could remain loose in their place resulting in elongation of stud holes. It is these factors that ultimately lead to the detachment of wheels from the vehicle.

Thus, wheel loss is majorly attributed to insufficient clamping force, which is possible due to the presence of dirt or damage between mating surfaces, low initial tightening torque and over-tightening. Reduced clamping force causes movement at the interface of wheel and hub and this can lead to loss of tension around the studs and bolts.

Following is a comprehensive list of reasons why wheel fixings can loosen:

Insufficient tightening of wheel fixing, leading to fret and wear of wheel.

Contaminants such as rust/scale, dirt or paint on the mating surfaces. This problem can be countered by regular cleaning and maintenance of contact surfaces.

Many drivers and technicians believe that applying extra pressure will prevent wheel nuts from coming loose. Over-tightening of wheel fixing leads to broken or stretched studs and causes them to be pulled through the hub. Irrespective of whether more or less torque is applied, when the material’s elastic material is exceeded it will result in stud failure

The torque wrench has been inaccurately calibrated or the calibration date has expired

Wheel fasteners have been used but their tightness hasn’t been maintained

Incompatible wheels have been fitted together

Unserviceable components and wheels have been fitted together

Interfaces and threads have not been lubricated adequately. If the initial clamping proves to be inadequate, it is mostly due to high friction loss and this problem can be solved by using the appropriate quantity of lubrication.

If lubrication is either applied incorrectly or excessively, it can lead to rapid deterioration of the mating surfaces of wheels.

Corroded wheel studs.

If studs have not been pressed completely into the hub or nuts are loose.

The assembled components are not in their right place.

The assembly of components is inappropriate relating to the torque and procedure applied.

Worn Wheel Spigots.

Seized or fractured wheel nuts washers.

Air impact tools when used incorrectly can cause issues, such as cracked nuts and washers and cross-threading. This is one of the many factors that torque depends on. Whether the torque applied is less or more depends on many variables and the contribution of each cannot be measured exactly.

A wrong sequence of tightening has been employed.

Variations in temperature can alter the surfaces which are in maximum contact with each other. If the surfaces melt, it can result in components getting misaligned thereby reducing the effective clamping load exerted on the wheel

While it is difficult to completely prevent the above problems from developing, it is however possible to detect them in time and prevent them from becoming bigger issues. With proper maintenance, the issue of wheel loss can be tackled effectively.

At Parma Group, we have a wide range of products that have been used extensively to increase the safety of vehicles on the road. Our products are of the required quality and standard to ensure that wheels are secured correctly.

Contact us today to know more about our products.


Wheel Safety Guide: Preventing Wheel Loss

In an earlier blog post, we laid out the reasons that can potentially lead to wheel loss. Understanding the reasons for wheel loss is essential, especially for businesses that heavily rely on a fleet of vehicles to go about their day to day functioning.

However, wheel loss is not just about ensuring businesses can continue to operate effectively. The issue of wheel detachment is also a lot more serious, as events like this can put another’s life at stake on the road.

Responsibilities towards Wheel Security


It is the legal responsibility of the driver of a commercial vehicle to ensure that it is free from any visible defects when it is about to be driven on the road. Any defects that are identified should be duly reported in writing.

This requires the drivers of the vehicle to carry out a careful visual inspection of the wheels and to rectify any possible defect that can cause a hindrance to the movement of wheels.

Drivers and Vehicle Standards Agency (DVSA) and Police officers have been vested with the authority to issue fixed penalty notices if these responsibilities are not adhered to.

Defective wheels and fixings attract a fixed penalty notice for a construction and use offence. Upon being served with such a notice by the examiner, the vehicle can be prohibited from being driven on the road.

From the nature of vehicle defects, the culpability of the driver will be determined and this remains to be the primary consideration when a fixed penalty notice is being served for a construction and use offence.


Operators are required to comply with this essential requirement of operator licensing, which is to maintain their vehicles in a roadworthy and safe condition. The DVSA and Traffic commissioners take strict action against those operators who follow a poor maintenance regime for their vehicles.

It is expected of the operators to make sure that all maintenance policies are being implemented, so as to prevent wheel defects from occurring. It is also recommended that all staff are properly trained in procedures concerning maintenance.

Third Party Contractors

It is common for operators to outsource the responsibility of vehicle maintenance to third party contractors. In these cases, the operators need to ensure that the necessary maintenance tasks are being carried out.

Operators are advised to request written copies of fitment policies and wheel inspection from third-party contractors. Operators may need to attach these copies in the contractual agreements that are signed between the two parties.

Operators should also perform spot checks to make sure that the contractors are adhering to the maintenance policies that have been framed.

It is worth remembering that irrespective of whether a vehicle’s maintenance has been outsourced to a third party or not, it is the operator’s responsibility to make sure that the vehicle is being maintained in the right condition.

Essential Checks

The drivers need to perform several checks before they can drive the vehicle on the road and they are also required to report any visible defects in writing. Following are some of the checks that should be performed related to wheels:

Visible damage to studs, nuts and other components

Cracked washers, nuts, wheels etc

Elongated stud holes

Distorted rims

Signs of wheels becoming loose

Presence of bright metal in the area of washer and nut seating

Visible rust in the washer and nut area

Relative shift in position of wheel nut indicators, if any

Blocked ventilation holes

If the driver detects any loosening of wheels, they should check them physically. A calibrated torque wrench should be used by an individual who is adequately trained to perform this task.

If wheel security has to be checked when the vehicle is away from the vehicle depot, the driver should make use of a socket and bar, preferably the one supplied by the manufacturer. They should make use of a bar that doesn’t exceed the length of 500mm.

In addition to the above checks, a driver should also be trained to conduct the following responsibilities:

Setting a torque wrench correctly

Being aware of the manufacturers recommendations regarding the correct torque setting for the specific vehicle and model

To learn the appropriate method of using a torque wrench

To know when to stop applying pressure once the necessary amount has been applied, according to the setting on the torque wrench

Looking for signs of loose wheel nuts

Once the wheel nuts have been adequately tightened, the torque wrench has to be reset to zero

If any defect is spotted, it should be investigated and rectified before the vehicle is driven

If wheel nuts are found to be loose, the wheels should be removed and a competent person should examine the removed components to determine the reason behind the loosening of the wheel nuts.

Wheel Tightening Procedure

Wheels need to be fitted in a way that leaves scope for any expansion or contraction of metal due to the heat that the arrangement is subjected to. If any component has been removed and refitted, care should be taken to ensure that they have been correctly installed before the wheel is fitted again.


Light Engine oil should be used to lubricate the threads of the wheel studs. A drop of oil should be placed between the nut and captive washer.

Wheels should never be painted before mounting them onto the assembly.

Only tools that are specifically meant for cleaning should be used. The contact of sharp objects such as nail gun, with the threads or mating surfaces should be avoided.

Wheel Fitment

The wheels should be carefully and squarely fitted over the studs so as to avoid damage to its threads.

Initially the wheel nuts should be fastened by hand.

Power tools should only be used during the initial phase of tightening. Further tightening should be provided with the help of a torque wrench. It must be properly calibrated and in good condition.

 When using an air wrench to apply torque, airflow should be kept to a minimum setting. The nut should be run down to the wheel hub and precaution must be taken to ensure that it isn’t over-tightened. 

The torque wrench should be set according to the instructions set by the manufacturer in the manual. The socket used should be of the correct size and depth.

The wheel should be lowered to the ground before the final tightening of wheel nuts is carried out to achieve the correct clamping force.

The wheel nuts should be tightened in the correct sequence as illustrated and should be set to the correct torque.

Over tightening of wheel nuts will be indicated by the fact that the nut doesn’t move during the procedure of applying torque.

Parma Group is dedicated to increasing vehicle safety on the road by providing vehicle accessories manufactured to match the required standards of quality and design.

Contact us today and make your vehicles more roadworthy.


Four Ways of Reducing the Rising Cost of Running a Fleet

After the Brexit vote, many UK SMEs have had to face rising costs, which has resulted in revenue dropping a considerable amount for numerous businesses.

These two economic factors have started to pile on the pressure for businesses that highly rely on a fleet of vehicles to carry out their fundamental operations.

The question that arises here is this: what can these SMEs do to reduce costs and protect themselves from the impending impact of Brexit, especially when it comes to their reliance on fleet vehicles?

Our team of experts at Parma Group have come up with four ways of reducing the rising cost of running a fleet:

1: Staying On Top Of Maintenance

The way your fleets are maintained has a huge impact on its fuel efficiency. Dirty engines tend to use more fuel, while wheels that are worn out, or those that do not have wheel nut safety installed can have a negative impact on your vehicles and eventually your business.

Additionally, poor understanding and application of maintenance techniques can also result in your business spending more money than needed. Hence, it is always advisable to keep on top your maintenance game, as prevention is always better than cure!

Having your fleets property managed and maintained will help you to ensure that they are running efficiently and most importantly, cost effectively.

2: Optimising through telematics

When you attach telematics, SMEs gain access to a rather huge, intricate set of fleet data. For example, people that are responsible for fleet management will have a better understanding of the routes being taken by their drivers, how efficient their driving is with respect to fuel consumption and how average speeds are impacting overall efficiency.

With this data, SMEs can improve their drivers’ overall performance. Alongside this, they can also monitor their drivers’ full journey details, which includes pence per mile calculations, without the need for receipts.

3: Use of Technology

Technology is a crucial part of most businesses today, and the use of it for the majority of sectors plays a vital role in making businesses efficient and reliable.

Similarly, we believe that technology can be very helpful for fleet managers to improve the productivity of their operations.

However, if fleet managers want to do this, they need to have complete access to comprehensive information (MI) protocols and processes, so that they can gather and analyse data effectively.

With an ability to analyse fleet data, SMEs can get back get in the driving seat and control cash management effectively. Access to fleet data will help businesses to work out which fleet is inefficient when it comes to fuel and maintenance, meaning they can make the necessary adjustments to improve.

4: Opting for a Fuel Card Solution

To save time and effort, your business should look into using a fuel card solution, if it isn't already. If you're not too sure what is involved, don't worry, as we will explain the basics below.

When a business works with a fuel card provider, they are given fuel cards which they issue to their employees. These fuel cards can be used in lieu of credit cards or cash at many petrol stations across the country.

A vast amount of petrol stations are involved with the fuel card scheme and locating refuelling points is super easy thanks to smartphone apps. But it's unlikely your employees will even need to use an app, as huge names such as Shell, Texaco, BP and Esso are a part of fuel card schemes.

Fuel cards are fantastic as they are a hassle-free payment solution, meaning companies don't need to deal with hundreds of invoices for fuel as they are billed directly.

Making your fleet operations efficient is not just about being cost effective and saving money either, as your business will also be saving precious time. And time is money, after all...

At Parma Group, we make sure that we are not only helping UK SMEs to save costs on their fleet operations, as there is far more at stake when it comes to logistics. Our aim is to make every road journey a better experience, and we play our part by providing wheel safety products to companies that are often behind the wheel


Minibus Safety what equipment do I need?

Remaining compliant and within the law is an important consideration for any minibus operator, we are often asked by companies what safety equipment do I need to be compliant, Whereas this list is not intended to be exhaustive it includes products that we are able to assist you with.

Fire Extinguishers

Schedule 7 of the Road Vehicles (Construction and Use) Regulations 1986 states that Minibuses must have a fire extinguisher that conforms to BS5423 (more recent legislation relating to fire extinguishers mean it must also conform to BS EN3 1996)

It is recommended that an extinguisher filled with Foam and must have a minimum test rating of 8A and 21B. Halon extinguishers are no longer legal in vehicles. A suitable one can be found here

If some passengers are using wheelchairs then two extinguishers should be carried aboard the vehicle one being in the passenger section of the vehicle.

Extinguishers should be tested normally once a year, some may have an expiry date and once this is reached they should be replaced.

It is advised that drivers are trained in the use of fire extinguishers and know where they are in the vehicle also the evacuation of the vehicle in the event of fire.

First Aid Kits

The same legislation also states that Minibuses must also carry a firs aid kit, there are several versions of PSV/PCV first aid kit available but they must include as a minimum the following items

10 x Antiseptic wipes (foil Backed)

1 x Conforming bandage (not less than 7.5cm wide

2 x Triangular bandages

3 x Large sterile unmediated ambulance dressing (not less than 15cm x 20cm)

2 x Sterile eye pads with attachments

12 x Assorted safety pins

1 x packet assorted adhesive dressings

1 x pair disposable gloves

1 x pair of rust free blunt-ended scissors

One of our most popular first aid kits which complies with this can be found here

All items in the first aid kit need to be kept in date if the date has passed they need to be replaced, if any items are used they also need to be replaced before the vehicle is used again.

The items should be kept in a suitable container which is clearly marked as a first aid kit and the driver should know where in the vehicles this is kept.

Safety Signs

There are a number of safety signs that should displayed in the vehicle so that all passengers can clearly see, a No-Smoking sign has been a legal requirement for over a decade now. Also it is the responsibility of the operator to ensure all passengers wear seatbelts while travelling on the vehicle, this can be done by an announcement before the journey begins but an easier alternative is to place a seat belt sign/sticker within sight of each seat which has a seat belt fitted.

We supply various safety signs for vehicles and they can be viewed here

When carrying school children it is legal requirement to display a school bus sign both at the front and the rear of the vehicle.

These need to be reflective, the front should be a minimum of 25cm x 25cm and the rear a minimum of 45cm x 45cm.

When there are no children on the bus these should be removed, there are several different fixing methods available and these can be viewed here


Why do wheels come off HGV and PCV’s and does it matter?

Having been involved in the Heavy Goods Vehicle (HGV) and Passenger Carrying Vehicles (PCV) industry for over 20 years I have always been conscious that wheel loss has been a long standing industry problem however it hadn’t really affected me, that changed a few weeks ago.

Driving along a busy dual carriageway with my family I was suddenly aware of a wheel leave a coach in front of me cross both carriage ways and run up the embankment on the other side.

Does wheel loss matter? If I had been travelling a little faster that wheel would have hit my car and possible hurt my family or myself. It mattered to the people travelling on the coach as their excursion was interrupted and it mattered to the operator and driver who had to sort out the problem.

Still don’t think it is a problem watch this short clip I found on Youtube,

So why do wheels come off?

Having spoken to many operators some have never lost a wheel in forty years of business another I spoke to had lost a wheel which caused a fatality, there are several reasons why wheels become detached from HGV and PSV vehicles, some of which I list below:

Poor Maintenance – Possible the most obvious cause and the easiest to remedy, wheels and studs need to be checked for defect before fitment there should be no cracks in the wheel and stud holes should not be elongated. The wheel and hub need to be free of rust and any loose paint wire brushed off, any rust on the studs should also be removed and the studs should lightly oiled.

Stretched Studs – Wheels are held on by a finite clamping force. When fitting wheels the nuts should be wound onto the stud by hand and then tightened to the correct torque with a torque wrench this varies between 500Nm- 850Nm. If a power wrench is used to fit the wheel there is a danger of over torqueing and stretching the stud, this will cause the stud to lose its elasticity and could lose clamping force.

Change of Temperature – If a vehicle is driving in an inner city it will be doing a lot of braking this can cause the wheel and hubs to become hot, the same is if the vehicle is driving in very hilly or mountainous areas. If there is then a sudden storm with heavy rain causing puddles, floods etc. there is a possibility the wheels will come into sudden contact with cold water which will cause the steel to contract and wheel to lose torque.

There are other possible reasons why wheels become detached, there also tried and proven ways to prevent this happening. Apart from good maintenance there are several products on the market that can prevent operators becoming a victim of wheel loss.


What do I need to look for in a Safety Helmet?

A safety helmet is required where these is a risk of being injures by falling objects.

Shells are primarily made using UV stabilised high density polyethylene (HDPE) or Acrylonitrile Butadiene Styrene (ABS), harneses are made using low density polyethylene or Terylene webbing.

To comply with European standard EN397 2012 all helmets must be marked with;

Size or size range in CM on both shell and harness.

Informative label with specified working on shell material eg ABS, HDPE etc.

The year and quarter (or month) of manufacture.

It is not recommended that helmets should be used 5 year after the date of manufacture.


What ArmourAll wipe should I be using?

Dashboard Wipes

ArmorAll® Matt Finish Dashboard Wipes are a quick and easy way to clean dashboards and trims without adding shine. The extra-strength wipes are specially formulated to clean vinyl, rubber and plastic surfaces. They can also be used for many non-automotive applications. They are non-toxic and can be easily disposed of. Highly efficient, just one wipe can treat an entire dashboard.

All Round Wipes

As a result of the increasing consumer demand for convenience, ease of use and efficiency, wipes have become an extremely popular product form. ArmorAll® was the first to introduce ArmorAll® All Round Wipes to the automotive category.

Protective Clothing