Your guide to Car Tyres

Posted on December 2nd, 2013 by GEM Motoring Assist

You might not think that car tyres are the most invigorating purchase but your life does depend on their effectiveness. Rob Marshall advises on how to buy and look after them.

Car tryes

Even the most advanced traction control, skid prevention and anti-lock braking systems cannot compensate for worn-out or incorrect car tyres. As the contact patch between an average tyre and the road can fit comfortably on a sheet of A4 paper, it is essential that they are maintained. While this is imperative from a safety perspective, it can also save you money, because you will need to buy tyres less often.


Keeping your car tyres in good condition is every driver’s legal responsibility Tyre pressures should be checked at least once every week but, because air expands as the tyre warms, check them before embarking on your first journey of the day.

Tyre pressure

Maintaining the correct tyre pressure is vital for safety, longer tyre life and to keep on the right side of the law.

Over-inflating a car tyre can reduce its contact area with the road, which will impair the vehicle’s cornering ability. Under-inflation will waste fuel, cause poor handling and, in extreme cases, the tyre can overheat internally and fail. The car’s handbook should detail the correct pressures.

Once the tread depth reduces to approximately 3.0mm, its stopping ability is reduced substantially and so it is wise to visit a tyre fitter before the minimum 1.6mm legal limit is reached.

Your guide to Car Tyres

The tyre tread should wear evenly. This tyre has worn excessively on its right side, indicating that the suspension geometry (including ‘tracking’) needs attention.

Car tyres can also be damaged by abuse. Striking hard edges, such as kerbs, might not only damage the tyre internally but also the suspension geometry could be knocked out of its optimum alignment. In either case, car tyre life will be compromised.

If used infrequently, car tyres can suffer from aging long before the tread has worn down. Although minor perishing in the sidewalls is acceptable, deep cracks indicate advanced deterioration and you should check the inside edges too. Regardless of their condition, you should replace a car tyre, when it reaches between seven and ten years old. 

Tyre damage
Tyres deteriorate with age and so yours should be inspected regularly.


When you come to buy tyres, it can be difficult to decide on the benefits of a premium car tyre brand against a budget one, because tyres appear to look so similar. Yet, they are not. New EU labelling, effective from November 2012, will help to raise awareness of different performance potentials between the various car tyre manufacturers. For the majority of unmodified vehicles, you should approach a tyre fitter for advice and purchase suitable car tyres that have the same size, load index and speed rating to those fitted originally to your car.

Tyre jargon
Tyre jargon explained.

To obtain the best deal, replace four tyres at a time and, if you shop around for quotations, do not forget to ask the tyre fitter to include the cost of fitting, VAT, balancing and a new tyre valve. Consider investing in a set of winter tyres, as the latest types can be used all year round. 

Schrader valve
Unless your car is fitted with Tyre Pressure Monitoring Sensors, a new Schrader valve should be fitted every time you buy tyres.

The tyre choices of most motorists are often dictated by their cost. Budget tyres’ performance and longevity is often inferior to that of the premium brands. Your tyre fitter can advise which premium car tyre companies offer an alternative budget brand that still incorporates the latest in tyre development.

Tyre balancing
After being fitted to the rim, new tyres require balancing. Tyres can become imbalanced as they wear, which can cause an uncomfortable vibration to permeate the car at speed.