Why is Timing Belt Replacement So Important?

If you've ever worked with us - or any other highly accredited repair shop, for that matter - before, you probably have been asked at your car's first visit when the last time its timing belt was changed. Auto technicians who emphasize preventive car maintenance pay special attention to timing belt maintenance, and for good reason. Imagine the following scenario...

Your six-year-old vehicle is starting to show a bit of wear and tear, but everything mechanical still works fine, so maintenance gets pushed to the back burner. Until it doesn't. Specifically, the engine suddenly goes dead silent one fine day, and you find that your vehicles timing belt failed!

Due to the damage the broken timing belt has caused, not only do you have to pay for the tow and the belt replacement, but also a costly valve job, because there's no compression on two cylinders. You're one of the unfortunate car owners with an "interference engine" -- an engine that can leave one or more valves still propped open far enough to contact a piston when the belt parts. Sadly, car sales brochures don't list whether or not an engine might suffer catastrophic damage if the belt goes.


In most cases, this bit of unpleasantness could have been prevented with timely maintenance. It's best to replace the timing belt according to your vehicle manufacturer's recommended schedule. Some rarer engines -- like those in more expensive models -- still use timing chains, rather than belts, like they did back in the day before the popularity of overhead camshafts. Unlike belts, timing chains usually don't have a routine replacement interval, but for most car owners, regular timing belt replacement is critical.

The timing belt (or chain) is the sole component that keeps the camshaft (make that camshafts on a DOHC or V-type OHC engine) and crankshaft in sync. So replacing this cogged reinforced-rubber belt at regular intervals -- generally every 60,000 miles unless the car manufacturer specifies longer -- is a lot less expensive and aggravating than having it break first. To find out what your car's maintenance schedule is, consult with us here at Cars for Keeps or read the owner's manual.