Flat Tappet Cams

[JosephHarmon]

The pre 2000 yr model N* engines were all flat tappet. Revisions to the heads used a roller re-design to post 1999 engines to solve this some what common problem.

This does only occur on the exhaust cam valve buckets and when it does is takes out the ex. cam as well as the bucket.

This was a part failure issue and not really a oil problem. Manufacturer shortages lead to quality control issues with the valve bucket & cam tempering.

 

[Timber_Wolf]

So basically what you're saying is that any major oil will do because possible flat cam lobes on my type of engine later on down the road have little to do with the oil i'm pouring in the crankcase. Oh boy

 

[Brons2]

Flat tappet cams, you make the rocking world go round!

Or is it my cam lobes that you make go round?

Anyway, I recommend Rotella, or if you can find some of the older Mobil 1 High Mileage that is SL rated. A less conventional, but equally effective choice would be the John Deere Plus 50 10w30. It's got SM, SL and SJ API ratings for gasoline engines.

https://jdparts.deere.com/partsmkt/document/english/pmac/5565_fb_Plus5015W40_0W40.htm#_Plus-50%E2%84%A2_II_Premium