Customer Ratings & Reviews

Use this in an 02 Duramax, has a sticks well to metal surfaces.

It's very oily, and quite slippery. Seems to lack all stickiness or roughness.

Good oil i change it out at 5k

Great stuff

I have been using this in my 6.7 Cummins and my farm tractor since 2015 and wouldn’t use anything else. Great product

This is great oil. Just traded in my 2019 mack and the guy that appraised my trade in said he has never seen a engine with 800,000 miles on it that clean inside. I do 60,000 mile oil changes and have never seen the oil look stressed.

Best oil on the market.

I really do swear by amsoil, their fluids hold up and definitely are worth it. Id run mobil delvac in my LBZ Duramax for many years but it just seemed like itd never hold up like it should and would seem to burn off. I tries amsoil and never looked back. Whenever its time to change my oil, not only does it still have great lubricity, I drain out the same amount that I put in and it holds up even if I’m busy and cant change it immediately. It also makes my engine run a lot more quiet. I definitely recommend this stuff, if you love your truck or machine, you want to make sure its well lubricated so its not wearing excessively and will be around beyond its potential. Give er the good stuff, Amsoil is that good stuff!

I have used 15-40 in my Chevy Duramax since I bought it, quieted it down, lowered temps and overall exceeded my expectations!

Great company great product speedy delivery made in the USA!

I do one oil change a year on my 2007 Dodge Cummins, and this oil is just incredible. Probably a little overkill for the annual mileage but worth every penny.

Best of the best

This oil is a great price and i recommend this product

This oil is the best you can get. I trust it with all my engines which include diesel, gas and outboard boat. Can’t go wrong with their oil and their other products.

See above

Been running this in my Ram 2500 with the cummins for a while. Oil stays clean and if you run a bypass system you can run this oil for 20K plus miles.

I put Amsoil in everything I own. People complain about the cost, but I can go 1 year+ between oil changes in my Duramax Diesel. People don't realize engines with turbos break down oils a lot quicker because of the intense heat (1700 degrees). Oil circulates through the turbo, Amsoil does not break down like other oils in that kind of temperature.

Have used Amsoil in my Dodge Cummings engine for seven (7) years. Maintains higher oil pressure at an idle than other engine oils. When having the injectors and valves adjusted, my mechanic tells me my upper engine is the cleanest he has ever see that has 228,000 miles on it. Rich Aubuchon owner

Happy with the oil I change it at 5k.

This is the only oil I have ran in my truck since the day I bought it - the truck currently has 267,000 miles of all this oil in it. Very pleased!