Customer Ratings & Reviews

I tow approx 10k lbs pretty consistently (40-50% of my miles) and have always used Amsoil for the extended drain interval. With about 40k mi on my truck and approx 15k miles on my oil, I decided to send my oil to blackstone for analysis. I’ll spare you all of the details but will tell you that they noted that I could safely extend my oil change interval out approx 10k more miles, taking the oil life to 25k miles. While they may be true, I just stick with annual oil changes to keep it simple.

Best diesel oil yet. Engine idles smoother and feels like acceleration is faster. Cold weather starts are no problem. Highly recommend.

Been using Amsoil for many years! Best quality product on the market for synthetic oil.

I use the signature series diesel oil in my powerstroke , and i use this oil in our f150 - great oil results in both.

Have never used any other oil in my Duramax and will never. Amsoil makes having an account and ordering online super easy. Use in our Triton V10 motor home, GMC Denali, Jeep Wrangler, ‘05 Duramax, Honda Generator, stihl blower etc. lifer!

Fantastic oil, been using it for years.

12,000 miles on last oil change Amsoil oil still looked great

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.