Schaeffer Manufacturing Co. 0700CK4-006S SynShield Durability Advantage 15W-40 Diesel Engine Oil, 1-Gallon Bottle

Run this product in my 2001 Ford power stroke with a 7.3l , 220 on the clock and it started to run not as smooth as it use to . Understandable with the miles. Frend of mine ask me if I would try it. I said yeah sure until I seen the difference in price. So I was like ahhh no that's ok ...he laughed and said I have a couple of gallons, try it for free and if you don't like how smooth your engine will run then you don't have to pay me for the oil ...I said ok I'll do that. All I can say is that it is well worth the price . I was amazed at how much smoother and cleaner sounding my engine was running if that makes sense. Idles so smooth and starts easier. Been in my truck for about 2000 miles now and I swear it keeps getting better the more I drive it . The turbo even sounds better , definitely recommend running on an older diesel engine. Not sure about newer diesels because I don't own one but I'm sure it can only be a great product for new engines as well

Owning a Diesel engine, and researching toxic of oil for the engine, I settled on this product. The “oil geek” YT channel teachings, Is one venues of wisdom I use on ail related concerns. This has a cleanser trait most others oils do NOT. It's one of the better products HGH quality for our Diesel engines. I HIGHLY suggest change your Diesel engine oils & filter, 4K Miles. It's expensive yet the thing will last 500K miles or MORE, if you maintain it right. Diesel engines create SOOT and so the manuals say 10K miles, NO FLIPPIN way!! 4K Miles MAX. Unless you put in an oil bypass filter setup. Then double it. All example I seen of diesels lasting 500K-900K Miles were #1 secret, Change oil / filter Ofter!!!!

Best oil hands down for my 6.7 power stroke

My 25 year-old 7.3 L turbo diesel picked up 3 1/2 miles per gallon increase engine noise decreased couldn’t be happier with it

I stand by the product with several cars! Once you have the car, change the oil & replace with this product - first oil change! Your engine will hum, run very smooth & crank smoothly (even in the harshest weather) Excellent value for the price and you can run an extra 1k miles before changing oil with this product.

Best diesel oil ever.

She oil does a great job with oil quality and fair pricing for a high performance oriented oil. This oil helps out significantly on my street car that has a junkyard engine in it since running this oil my engine has stayed nice and quiet, and even while changing the oil at shorter increments for this particular vehicle, it is still quite affordable.

Watch the Diesel oil comparisons on YouT-be.. This is the best imo.