ocpdba,

Yes, as I've said in another post, I've seen timing chain stretch in recommended interval engines versus OCD interval engines, it virtually does not stretch in the OCD engines.

The original engine in my 240D went 380,000 miles with 3K oil changes. It actually was still running pretty good, but the rear main seal had worn to a point where it was no longer touching the crankshaft. It would have been dumb to pull the engine and ONLY replace the seal. It was pretty impressive what everything looked like. I took apart another 240D with 200,000 and recommended interval oil changes that was really worn out.

I reitierate, however, for most people the recommended interval will provide satisfaction.

Have a great day,