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Timing Belts

How do I know if my car has one?

Check your owner's handbook, or ask us.

How long do they last? For most cars it is 60,000 miles or 4 years, whichever comes first. On some vehicles the maintenance interval is as low as 30,000 miles and some are over 100,000 miles. Check your owner's handbook, or ask us. The timing belt job can be costly and some owners may sell their vehicle before having this work done. Most of the time there is no way to tell the work has been done by looking at the engine. When buying a used vehicle see if the seller can provide documentation showing the timing belt has been changed. If you bought the vehicle without a service history, you may be safe to have the belt changed as soon as possible.

What happens if it breaks?

Depending on whether your engine is an "interference" or "non-interference, or free-running engine" you may or may not experience major engine damage.

What happens on a "non-interference or free-running" engine?

If the timing belt breaks on a free-running engine the engine stops, and your greatest additional expense may be a towing fee to get your car to the shop. No mechanical damage occurs and the installation of a new belt is usually all that is needed to get you on your way.

What happens on a "interference" engine?

If the timing belt breaks on an interference engine, major engine damage usually does occur. It most commonly involves open valves being struck by pistons as the engine continues to turn to a stop after the belt breaks and the camshaft stops opening and closing the valves. The result is an otherwise needless, expensive repair that could have been avoided had the belt been changed at the recommended service interval. In extreme cases, a complete replacement engine may be required.

Is there anything else I should ask about when replacing my timing belt at the normal service interval?

When having your timing belt replaced it is a good idea service the following:

• Serpentine or engine drive belts. Have your serpentine or engine drive belts replaced because they have to come off to get to the timing belt, so there is usually no extra labor in replacing them.

• Front engine seals. Have your front engine oil seals replaced, as equipped- the cam seals, crankshaft seal, intermediate shaft seal, and countershaft seals. Because if you don't your belt may not make it through the next life cycle. High engine temperatures cause these seals to become hard and brittle allowing them to leak. When this happens engine oil will saturate the timing belt causing it to break.

• Replace your water pump. Once the timing belt is off, for most cars the water pump takes very little additional time to replace. Usually, the greater part of the additional expense is in the part itself! If the pump is not replaced and fails, the whole job has to be done over again to gain access to the pump.

• Service your cooling system. When taking off the water pump, the cooling system has to be drained. So, it's a good idea to add new anti-freeze, a new thermostat and check your hoses at the same time.