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

Swapped to schaeffers from Rotella 15w40 and noticed increased oil pressure, slightly better fuel economy, and a quite engine. I was quite impressed. Its really good oil, but... the downside is the price, I recommend going through a nearby sales rep as the prices are exponentially cheaper than buying from a 3rd party vendor such as Amazon, Napa, O Reillys etc.

For Hubbys stuff..

Love this oil. Great quality

Top of the line oil for the Powerstroke.

This is a good product, this price was better than what Schaeffer direct offered. To get better, my order would have to be a lot bigger. The convenience of delivery was helpful. At one time there was much less costly Chinese alternative but no longer available and it didnt have the ratings CK that this purchase offered.

Great fuel economy, incredible oil!

I tried this due to not being able to find Rottela T5 in the stores. For me this will be a permanent switch. My 6.0 starts easier runs quieter and seems to get a little better fuel milage.

Really good oil 5/5

Dont buy

Travel between Texas and Wisconsin several times a year. This oil has out performed all others hands down. My 2013 F-350 is a happy machine. Mileage Increased also by a mile per gallon.