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

Its green

This oil company is the best in the biz!

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

For Hubbys stuff..

This is a good oil, but it is very expensive for the value. Lucas Oil 10299 SAE 15W-40 CJ-4 Synthetic Motor Oil works just as good for half the cost. Schaeffer oil is good but not worth the extra cost.

Use exclusively in my 2017 Ford 6.7 powerstroke. Great oil.

Good oil at a great price, well worth the investment as I plan on driving the tires off this thing. I was previously running Castrol Full Syn and switch. My idle oil pressure is now 10 PSI higher. I tested this on a brand new oil pump and used Castrol after replacement. Used Sheaffer on the next oil change and I am happy to see the oil pressure running hire..

The best oil money can buy. I use it in my 1999 dodge cummins diesel

I bought this oil for my 2019 GMC Sierra Duramax diesel, however my owners manual clearly states API CJ-4, ONLY!!! However, further on in my owners manual it includes CK-4??? It would stand to reason that API CK-4 rated oil would be superior to API CJ-4 as this rated oil is older and does not include the latest additives. GM needs to do a better job proofreading their manuals before issuing them with new trucks.

I have been driving diesels for 30 plus years and 1.5 million miles. I believe that this oil and all Schaffers products are the best Ive used. Since using this oil Ive had two b series Cummins go over 700,000 miles without touching the engine other than to adjust the valves. I use Schaffers in the tranny and differentials as well with same no failures results. I always rebuild my auto trannys at 300,000, clutches wear out no matter what, and shop said the externals look almost new each time.