Great product!

We’ve used the Signature Series diesel oil in all of our Ram & Ford trucks (and a Jeep GC) for 12+ years. Best oil on the market!

Outstanding ordering process online, very quick delivery and outstanding Packaging. What I do wish is for the members they would at least throw in a funnel with each shipment, Even if it was just a paper funnel

You definitely get what you pay for. This is the best oil that I've ever used in any of my vehicles.

Great product, exactly what I was looking for.

Use it in all of our vehicles. Been using it in my diesel trucks for years now and wouldn’t use anything else.

Great product truck running better than ever.

always fantastic

I ordered this case for my diesel pickup just in case the rumors that diesel engine oil is soon to be unavailable along with DEF fluid too. Since I recently changed my oil and filter this case will last me well over a year when you consider the extended interval between changes using Amsoil.

I purchased the 5/40 for my 2019 ram 2500 6.7 . The engine runs so much better and cooler . I’m sold I will buy for next oil change

I have looked up the reviews on the Internet and Amsoil comes out on top for the best in its class. I drive a diesel GMC 2500 and I want the best for my truck. AMSOIL 15W–40 and AMSOIL 5W–40 diesel winter time grade is the very best.

Excellent product and fast shipping.

Have seen tremendous decreases in wear metals in oil analysis, as well as increases in fuel economy vs. the other synthetics I have tried. No need for them anymore.

will continue to run this oil as long as i have this truck hopefully another 200,000 miles plus.

Always use amsoil, so worth it and do to the fact we can get twice as many miles out of an oil change it’s more cost efficient. Also so much better for your diesel motors. 400,000 miles on our 2009 dodge 2500 Cummins 6.7. We put 500 miles a day on it pulling a trailer everyday loaded down. No leaks and don’t burn oil and still runs like a champ!

Beat oil out there!! Would definitely recommend this product to anyone

This oil change I swapped to Amsoil. Just made a 500 mile vacation trip and was really happy to see that my 2020 Chevrolet 2500hd Duramax gained 2+ mpg after the oil change. I know that Amzoil doesn't make any mpg claims in their advertising but it sure showed up on my trip computer. With the current cost of diesel that makes my wallet a bit happier.

Just changed oil in our new Chevy Duramax 3500HD 3000 miles on truck. pulled 33 ft toy hauler to Colorado 1800 miles round trip an used 1/4 quart of oil. Will continue using Amsoil in all my engines.

i have used amsoil back from the 70's, i use all of these in all my stuff

Awesome oil been running this oil in my 2018 Ram 2500 since second oil change and currently at 97,000 miles.