Regularly checking the tread on all four of your tires can help diagnose potential problems. Check them at least once a month, as well as before and after long journeys.
Things to look out for:
Visible tread wear bars: You can only see these bars of hard rubber when your tire’s tread has become worn. If you can see them, your tires need replacing. If you’re not sure where they are, you’ll see a mark on the sidewall that indicates where to look.
Your tread is less than 1.6mm: Your treads must be at least 1.6mm deep around the tire’s circumference. Check them with a tread depth gauge (they aren’t expensive if you haven’t got one) and make sure you measure both the inside and outside of your treads.
Something’s lodged in the tread: Things get stuck in your tread all the time. Most of the time they’re easy to remove, but if you spot something that looks as if it’s gone through the rubber, like a nail, leave it in until you can get to a garage. Otherwise you’re likely to end up with a flat tire.
Tires are worn on the outside: If they’re worn on both of their edges, you might need to inflate them or check for leaks. Tires lose air naturally, but driving on underinflated tires uses more fuel and puts you at greater risk of accidents. If you notice that only the front tires have worn edges, you might be taking corners too quickly. Make sure you regularly check your tire pressure.
Tires are worn in the centre: If the centre of the tread is wearing more than the outer edges, you might have overinflated your tires. This can increase the risk of a tire blowout. Get a pressure gauge and then deflate to the recommended pressure level.
Uneven wear across a single tire: The wear patterns on your treads might indicate problems elsewhere. If you notice uneven patches of wear, or bald spots, you might need your wheels balanced or aligned. Sometimes bald spots indicate that your shocks are worn.
Uneven wear across all the tires: Your tires won’t wear out at the same rate. The front of your vehicle carries the engine and does most of the steering work, so tires on your front axle will wear out more quickly. If they seem to be wearing more than normal, you should have your suspension checked. If wear is greater on one side of the vehicle than the other, it might be time for an alignment.
Sawtoothed pattern on tire edges: If you notice that your tires have a sawtoothed or feathered appearance around the edges, the likely cause is erratic rubbing against the road. That’s a sign that you may need an alignment.