Originally posted by On the road again:
When was actually the last year regular motor oils stopped having zinc ?
I have used multigrade oils on my daily late 235 from 1995 until I switched to Rotella SAE 30 last year.
I got hydraulic lifters and never had any cam issues.
It seems the danger with cam failure is more about the break-in period.
Can anybody describe what happens during break-in without zinc in the oil that causes cams to eventually fail?
I believe it was 2005 or 2006, but I can't remember exactly.
The stories that I've read do say that they added the special oil supplement that was suggested by the cam manufacturer (in the cases I read, GM's EOS) as directed for the break in period, and then stopped adding it after break in was completed and ended up with a worn out cam 9-13 months later. Granted, these were mostly V-8's, and I'm sure that they were a little hotter than your everyday cam, and that the drivers were pushing things, but still...
