Checking your tyres regularly can save you both money and inconvenience.
Tyres that display wear patterns on the edges can indicate high load carrying or under inflation typically anything below 30 psi will cause both edges to wear. Front wheel drive vehicles in particular suffer from this type of wear, because of the weight of the engine and gearbox being directly over the front tyres. It is important to inflate tyres when cold and ensuring that your pressure is over 34psi will prevent this kind of wear.
Signs of abnormal wear down the centre of the tread area is an indicator of over inflation of the tyre. This causes the tread to take on a concave shape and reduces the amount of tread in contact with the road, which can also be detrimental to handling, especially in the wet. The reduced area of contact also causes a rapid wear of that part of the tread that is in contact with the road surface.
Tyres that are worn abnormally on either side of their tread are usually the product of bad wheel alignment or suspension problems. Kerbing of tyres or damage from poor quality road surfaces are the most common cause of wheel alignment and suspension issues.
Worn shock absorbers cause patchy wear on the tyres surface due to bouncing over bumps in the road. Wheel balance, play in wheel bearings and worn suspension joints can play a part in this also. Four-wheel-drive vehicles with worn shocks seem to be particularly prone to this type of wear.
Feathering of the edges of the tread is generally caused by excessive toe-in or toe-out which can usually be corrected by adjusting the alignment.