On my 1983 300SD (617.951) I did the first chain (and tensioner) change at 105k, as it was stretched 7 degrees. Lots of city driving, on and off the gas (sorry, diesel).

That replacement chain is now at 198,700 miles, so has, say, 94,000 miles on it and is stretched just one degree. Mostly freeway miles.

Oil and filter changes on both have been at 2,500 mile intervals using the cheapest big name dino oil I could find. Cannot speak for the first 44,000 miles on the first chain as those were run up by the original owner.

Which reminds me, I have to post my diesel timing piece on my web site soon....