Customer Ratings & Reviews

I did a test on my 2009 Cummins - I ran this oil with the Ea0 filter and tested it at a third party lab every 6,000 miles. Every test came back perfect until 24,000 mile interval - at this point, the test showed “slightly elevated” Molybdenum levels. The Certificate of Analysis for this specific test noted that the oil was still perfectly safe to run despite the slightly elevated Molybdenum. To summarize, this oil saves me money on oil changes and protects my diesel engine like no other on the market. Thank you and I love you AMSOIL!

I've known amsoil since the 70's, I trusted it then and I trust it now.

This stays clean looking a lot longer than anything else I've used. And for hotshot runs cross country it's a must for fuel economy

I use Amsoil in all my vehicles including motorcycles.

Only oil I use for my F250.

Have a 2009 duramax 364,000 miles runs like a champ. Would not use any other oil in it.

Have a 2001, dodge ram 2500 with a Cummins diesel and automatic transmission. I’ve been using this oil since I bought the truck in 2004 and have had zero oil related issues, and this truck is regularly, overloaded and overworked.

Amsoil is the best oil on market! Have had it tested after using and viscosity stands true! Only oil I use in all my motors and engines

This oil out performs the Ram suggested oil for the ecodiesel and the 2.5 gallon jug is the perfect size. Couple the oil with wax filter and it is a winning combination.

Great product been using amsoil for years now.

I've run this oil and Royal Purple synthetic 15w40. I do find Amsoil quietens my older deisel down better.

I have been running this oil since I bought the truck new. I only trust Amsoil in my truck.

Seems to be a great product. I'm only driving the truck about 8000 miles a year. So, I change the filter and add 2 quarts at 6 months, 1 complete change 1× a year. I haul a heavy pick-up camper, and prior a 30 ft 5th wheel. The engine is running great at 215,000 miles

Been using Amsoil’s 15w-40 on my Duramax for years and I absolutely love it. I can get 15-18k intervals out of it and it’s still got a couple thousand more miles left in it. Take care of your vehicle and it’ll take care of you… run amsoil

Great product with super fast shipping! If you have a tech question they are quick to respond to your email.

Have used Amsoil Diesel Oil in My 2005 F250 for 190,000 miles i would not use any thing else.

This is the first time I have used the signature series oil I always used the silver jug previously. I rate this oil so highly due to the instant noticeable increase in fuel economy after my most recent oil change. The big diesel runs at lower RPMs during all driving ranges and I have gained approximately 2mpg!

Love it

I've been using Amsoil in my 6.0 Powerstroke for almost two decades now highest quality oils available that's why I use it and that's why I recommend it

Great product have been using it for several years