Technical Information

Tread Depth

The legal minimum depth of the main grooves of a car, van and trailers up to 3500kg in weight is 1.6mm. This applies across the central three quarters of the breadth of tread and round the entire outer circumference of the tyre. But don't wait until you get to the legal minimum, Feltham Tyre Centre would recommend tyres are changed at a minimum of 2mm preferably 3mm.

TPMS (Tyre Pressure Monitoring System)

What is it?

TPMS stands for Tyre Pressure Monitoring System, it notifies you when your vehicle's tyre pressure is low or is going flat. A warning light will appear on your dashboard when tyre pressures change.

Why Is It Important?

TPMS can increase your safety on the road by improving your vehicle's handling, decreasing tyre wear, reducing braking distance and bettering fuel economy. It alerts you to pressure loss and preventative measures can be carried out.

If the TPMS warning light on your dashboard comes on, this should not be ignored as there may be a problem with the pressure in one or more of your tyres.

Check your tyre pressure when the light comes on – you can always get a free pressure check at Feltham Tyre Centre.

TPMS Valve

It is important that every time you have work done to your tyres, be it replacement or repaired, your TPMS valves are replaced in order to keep them in good condition

TPMS Sensor

If your TPMS valve sensor is faulty or the battery fails (the batteries have a lifespan of around 5-6 years) we have the ability to supply new sensors and reprogram so your TPMS system will carry on working as normal

Tyre Pressures

Correct tyre pressures are vital for safe handling and optimum braking, grip and tyre life.

Wrong Tyre Pressures (high or low) will cause more rapid wear and shorten tyre life.

Low Tyre Pressures: Under inflation is one of the leading causes of tyre failure. It can result in unnecessary tyre stress, irregular wear and possible loss of vehicle control, not only that, under inflation will increase fuel consumption.

High Tyre Pressures: Over inflation is also highly undesirable with risk from tyre blow out, may cause reduced comfort, and reduced stability in braking and cornering.

Pressures should be checked at least every two weeks and only when the tyres are cold. Accurate and reliable gauges are not expensive and will soon pay back their cost.

How tyre inflation affects tread-to-road contact

Underinflation

Overinflation

Proper inflation

Both underinflation and overinflation reduce tread contact with the road. Proper inflation ensures maximum contact

Wheel balancing

Safety is the main reason for balancing the wheels and tyres on your vehicle. Balancing will help ensure a smooth vibration free ride as well as improving tyre life.

When the wheels on your car have an imbalance, the most notable effect is that the steering wheel will vibrate in your hands or the seat vibrates. As tyre and wheel assembly is vibrating the contact pressure of the tyre on the road varies, which can cause irregular wear and will in turn result in premature tyre removal.

The wheels should be balanced when new tyres are fitted, any time that the tyre is removed from the aim and at regular intervals to take into account any variation in tyre balance from irregular wear.

Wheel Alignment

Correct alignment is critical to safety controlling your vehicle, braking stability, extending tyre life and ensuring a comfortable ride. It is extramely important that your vehicle's front wheels are aligned to the rear wheels, and where possible all four wheels should be aligned.

Symptoms of incorrect wheel alignment:

• Your vehicle pulls or drifts to one side when travelling in a straight line or when braking.
• Your steering wheel is not straight when driving on a level road.
• You hear unusual noises in your suspension system.
• The vehicle wanders from one side of a lane to another.
• Tyres are squealing on turns.
• The steering wheel does not return easily after a turn.
• Your tyres are wearing unevenly.

Exhausts & Catalytic Converters

Exhausts & Catalytic Converters - The exhaust system is one of the most hard working components on your vehicle. It is constantly in use while the engine is running. An exhaust system on most vehicles comprises of these sections:

• Manifold
• Front Downpipe
• Centre Section
• Rear Silencer Box
• Catalytic Converter (post 1993)

The rear silencer is the part of the exhaust that usually requires attention first. The reason for this is it is the furthest away from the engine and is most likely to be corroded by acidic moisture.

You will know you have a problem because your exhaust starts making a roaring noise, other noises to listen for include hissing, which indicates a cracking in the exhaust manifold, exhaust pipe or leaking gasket.

Catalytic Converters (cats for short) are now fitted to all cars to remove harmful pollution from the exhaust gases. It is an integral part of the engine performance system and sensors control the gases enteringand leaving the cat are controlled by the engine management system.

Cats are easily damaged by hitting solid engine can cause the cat to work ineffectively requiring replacement.

Tyre Law

There are severe penalties for offences relatingto the use of faulty tyres on vehicles.

In the case of any vehicle, except goods vehicles for every offence there is a fine at level 4 of the standard scale with dsicretionary desqualification and compulsory driving licence endorsement with 3 penalty points.

Level 4 is currently £2,500 and each faulty tyre is considered a seperate offence. Two faulty tyres equal £5,000.

Offences can relate to:

• Tread Depth: a tyre worn below the legal limit (1.6mm)
• Mixing: an incorrect mixture of radial and crossply tyres
• Inflation: a tyre not inflated to make it suitable for the purpose to which the motor vehicle or trailer is being put.
• Cuts: certain long and deep cuts as specified in regulation
• Lump, Bulges or Tears caused by separation or partial failure of the tyre structure
• Exposed Ply or Cord
• Unsuitability: regarding the use to which the motor vehicle or trailer is being put to the types of tyres fitted to its other wheels.

Monthly Tyre Health Check

We would recommend keeping your tyres in optimum conditions by following these simple rules.

• Check the pressure of your tyres when they are cold.
• Check the tread depth of your tyres. Legal minimum is 1.6mm.
• Check your tyres for damage. look for any cuts, cracks or bulges.
• Check the pressure and tread depth of your spare tyre.