Customer Ratings & Reviews

I have three diesel trucks and five diesel tractors, and all are serviced with Amsoil products. Besides extended oil changes, my engines stay clean and trouble free. I would never consider using anything else.

Increase oil pressure and smoother idle.

I have used this oil for over 18 years in a 7.3 diesel ford-350 4x4 and have had great performance in using it .The engine doesn't have to work as hard with Amsoil synthetic oil 5-40w it runs cooler and less RPMs for the same speed as other oils . If you're not using Amsoil synthetic oils in your engine and truck and or other motor vechicle your missing out on the best performance your motor Vechicles can give you ..

I really appreciate the ability to use the "My Garage" to identify the products and capacities listed for each of my vehicles. That with Amsoil's excellent write ups on their products gives me a piece of mind that I have the right fluids for each vehicle. This oil has all the additives my old truck's diesel needs to stay running for another 250,000 miles.

looks good. I will need more time to fully evaluate it.

Premium oil for a premium price. Works out in the long run for me with extended drain intervals. I use it in all my diesel business trucks.

I use amsoil in all my vehicles, even my lawn mower. This stuff is the bomb, less oil pressure due to better flow, and smother running etc...

Great oil for you engine can't go wrong with full synthetic. Other then manufacture recommendation on oil brand this is the only other brand I use. I'm still old school so 5k oil intervals is cheap insurance for a $67k truck. Oil itself is amazing compared to previous oil used at 5k miles drains Amsoil looks and feels great. Smoother engine idle and smoother engine operation at higher rpm range. I have a digital psi gauge installed and with Amsoil the engine oil psi has maintained same psi throughout the oil intervals the oil temperatures has dropped 8 degrees lower under same driving conditions. I know that's not a professional oil analysis but it's what I've got.

My 2016 F350 6.7L runs smoother on this oil

Excellent fluid, haven't used anything else for years, thanks

Amsoil is an ansome products.

I notice a big difference in mileage and how the truck ran after changing the factory oil to Amsoil. The mileage is up over brand X that I replaced. I've used Amsoil in all my diesel trucks, no complaints!

I have used this oil for many years in my 3500 GMC. A recent trip of 11000 km with the 25000 mile oil filter did not change the color of the oil it was still as if it came out of the container. Excellent starting in cold weather

Great oil at better than dealership prices. Why wouldnt you?

I don't know if my 2013 Ram diesel is protected better by using Amsoil motor oil, but I trust Amsoil research. I believe what Amsoil claims. I can only say this about Amsoil. Only time will tell as the engine ages.

I love this oil I rely on it with my lively hood. Great stuff.

2007 Dodge 6.7, engine never sounded smoother. Best investment I've made.

I would buy this top grade again because I once bought the XL grade and notice a slight drop in mileage.

I have been using Amzoil in my 2008 Dodge Ram 2500 since the first oil change. I currently have 147,000 miles on it and it doesn't burn a drop of oil, runs smooth and has a ton of power. I believe that using a quality oil with regular oil changes is the key. This stuff is not cheap! Neither is this truck! But to replace it is $68,000. I think the Amzoil is going to give me that quarter million mile mark.

Diesel