01 I’m worn out!
We’ll start with the obvious. You need to check your tyres regularly for wear and tread depth. We do mean regularly, not every few months. In the UK you need to have a minimum 1.6mm of tread depth across the central 3/4 of the tread and around the complete circumference of the tyre.
In fact, though, the performance starts to suffer once the tread depth falls below 3mm. Did you know that on wet roads it takes another two car lengths to stop from 50mph with 1.6mm of tread depth compared to 3mm?
You can also get 3 points on your licence and a £2,500 fine for having tyres below the minimum tread depth. In the US, requirements may vary between states, but the minimum tread depth is the same.
You can check tread depth using the edge of a coin. A UK 20p coin has an edge that’s just the right thickness. Seriously, though, get a proper tread gauge – they’re cheap enough and a lot more accurate.
02 Your tracking’s wrong, mate
Have a look at the wear across the tyres, particularly at the front. For this you need to turn the steering on to full lock so that you can see the full tread width. Is one shoulder worn more than the other?
That means the wheel alignment is incorrect, was incorrect in the past, or the tyres have been swapped at one point because of uneven wear.
The wheel alignment (tracking) is important. If you’ve hit a kerb or a big pothole, one wheel may be knocked slightly out of line so that it’s no longer pointing ahead at the right angle.
You may not notice it from the feel of the car. Sometimes it can affect the alignment of the steering wheel so that it’s no longer perfectly level as you drive in a straight line, sometimes not.
Wheel alignment is a pretty precise thing, and a couple of degrees here will make a big difference. You can’t just take a look from the front of your car, stroke your chin and think it looks OK.
If you’re suspicious, get it checked and fixed. It costs about half as much as a new tyre (or less) and it could save you (a) wearing out a set of front tyres at twice the rate, (b) driving a car that pulls this way and that, (c) landing a heavy fine for illegal tyre wear you hadn’t noticed.
03 No pressure
Tyre pressures are hard to gauge visually. Front tyres always look a little squashed at the base because that’s where the weight of the motor is – and tyre engineers have, after all, calculated the optimum pressure and contact patch.
The bottom line is that you can’t just go by the appearance. The pressure has to drop a lot for the appearance to change noticeably and you need to intervene before that happens.
When a tyre is underinflated the centre of the tread doesn’t make proper contact with the road and the sidewalls wear more heavily.
Your tyre wears out prematurely and doesn’t deliver the handling and stopping distances you’d expect.
And don’t overinflate your tyres in the hope that this means you can leave it longer before you check them again. Overinflated tyres don’t provide proper grip and handling, and this time the centre of the tread wears prematurely.
So get a pressure gauge, and check your tyre pressures regularly.
04 Ouch, that hurts
So when you get into the habit of checking your tyres every weekend you may spot other problems before they become full-blown disasters. Check for nails or screws embedded in the tyre between the tread blocks.
Sooner or later they may push through the carcass and cause a puncture – which usually happens in the middle of a wilderness somewhere.
If you find one and pull it out and the tyre goes flat, well, it’s better to find out on your front driveway than in the middle of nowhere.
Check too for bulges in the sidewall from kerb damage, or perishing in the rubber which indicates the tyre has aged past its useful age even if it still has enough tread depth.
No one likes paying for a new tyre, but it’s a lot less painful when it’s outside your own house and you didn’t just have to wait three hours for a tow truck.
05 Pull over!
If your car’s steering pulls under acceleration or under braking, or follows irregularities in the road, start with the tyres.
Old, worn tyres can sometimes be more prone to ‘tracking’ irregularities in the road surface than new ones, and if you have different tyre brands and degrees of wear on the front wheels, this may become more exaggerated.
No-one will be surprised to learn that you mustn’t mix crossply and radial tyre constructions on the same axle, but you can also hit problems if you mix modern types such as asymmetric and directional types, especially at the front.
These may steer in a straight line well enough at a constant speed but react very differently under braking and acceleration, causing the car to pull.
Just remember, your tyres are your friends. They can sometimes be tiresome (sorry), high-maintenance and expensive, but they do watch your back, day in, day out, and there might come a time when, like the very best friends you could possibly have, they save your life.