It's a general question. I've heard over time they "stretch" and need to be replaced and I've also heard that they never need to be replaced. Any clarification would be greatly appreciated.

 

my mercedes had a timing chain and it had to be replaced

 

At what mileage?

 

My daughter's POS Saturn did and it should have been done before it self-destructed. Valves stayed open pistons went up & down about twice Result was there was more metal in the pan than oil - Newer Saturns don't have that problem - so I've been told.

Had it replaced on our 93 Tracer at 90k miles - just to be safe.

 

It's because they have Honda motors in them now.

 

they say not to do it, i would say at about 150k- 180k.

 

Oddly enough, I don't see it on the maintenance schedule. However, I would definitely do it by 90K miles... sooner if you track/race the car.

When I was in high school, I had a Nissan Sentra (with a deisel engine) and the timing chain broke at about 110K miles. Not a cheap fix.

 

A good rule of thumb is about 100,000 miles to replace a metal timing chain in a normal street driven engine. Obviously cars with a lot of track miles should do this sooner. Being that this is an "interference" motor, if the chain breaks the valves will come into contact with the pistons and lead to a much more expensive repair.

 

A high quality chain with a good tension system should go the life of the engine without a problem. Even the timing chains on old V8's went for the life of the engine, usually over 100K miles.

 

I busted a chain on an old V8. 1970 Olds 442 motor to be exact. Just over 100,000 miles Bent a few valves. Ugly,