Schaeffer Manufacturing Co. 0700CK4-012 SynShield Durability Advantage 15W-40 Diesel Engine Oil, 12-Quart Bottle (Pack of 12)

Good oil.Had it before, but dropped after ingine start eating oil.Since bouthg different semi start using again.

Nice oil

I’ve put 110k miles on my truck over the last three yrs and finally switched to Schaefer’s. She’s instantly running more smoothly than I remember before the wear and tear. Impressive stuff. Should’ve started using it BEFORE all those miles but this has definitely made a notable improvement.

Theirs no better oil on the market

This oil company is the best in the biz!

Case leaking oil when it arrived

Used it for years in my gm crate works great

Read a lot of great things about this oil for use in my 6.0 PSD, just towed my travel trailer to Charleston SC and ran very well,oil temps alw a ys good even though we were in 95 ambient temps running 60-65 mph.

Love this oil Only oil I will run in my truck from now on Starts up better and runs quieter

Amazing product I run it in everything!