At what mileage does the timing belt/chain need to be changed? 04 Impala SS with 66K.

 

Timing chains do not have a service/maintenance interval. They very rarely fail.

 

They normally outlast the car. There were some plastic gears used in the 70s that failed but nothing in the last few decades.

 

Thanks for the replies guys! My 99 Acura TL got the timing belt changed at 105K as recommended by Acura so I was just curious.

 

One more question, (sorry it's my wife's car) does this car have an interference motor?

 

It's really not an issue. When timing chains do fail, they only slip a tooth or two and that is not enough to hurt anything. They just run really lousy or not start at all.

 

On the 3.8 the timing chain should last the life of the engine, They do not wear as fast as in the old days.

 

Is this true with the 07 3.5?

 

Yes. Generally, the only timing belts that require replacement is on overhead cam engines that use a belt and not a chain. Most timing chains, whether OHV (like my Impala) or overhead cam (like my F-150 and Escape) are designed for the life of the engine.

 

Does a chevy impala ls 08 have a timing chain on it?