Originally Posted by bigdave
I run Mobile 1 synthetic oil and it IS a chain not a belt and the tensioner design is good.
Why wouldn't the chain last forever ?
You Timing Chain HAS
During its life span, the metal in the chain tends to stretch a little bit. Over time(in your case - a LONG time) it stretches to a point that it becomes very sloppy, and Mobil 1 doesn't prevent this from happening. I don't mean to imply that this is your problem, as I don't really know the answer to this one, but it may be a contributing factor. Also, just for the record, how long have you owned this car and is it the orginal engine and transmission(not rebuilt)?