Customer Ratings & Reviews

I've been using Signature series 5w-30 for over twenty years and will use no-other because it simply continues to be the best available synthetic motor oil on the market. The mechanic I use puts it into my engine, transmission, radiator, and differential. I have a total of over one hundred thousand miles of trouble free driving on my vehicles.

I am a 15yr customer. I have been running AMSOIL in all my vehicles. One of my cars is a 97 Geo Metro with a 5 speed trans. The car has 320,000 miles on it. I use it daily to run errands. I didn't want to part with the 52 mpg so I rebuilt the engine. The transmission was hard to shift. After running amsoil 80-90w trans- oil for about a month it now shifts smooth. I have been driving both of my cars with confidence. I run amsoil 5w-20 signature series motor oil in both of my cars. The only negative I have is that I wish shipping was free. Jerry

Use it in my Corvette C6

AMSOIL synthetic is the best!

Title says it all. I bought this for my first oil change on my 2015 Ford Focus ST. I'm now on my second oil change using the same product. My engine oil temps run consistently 15-20 degrees cooler than before. Will never go back to another brand again.

Have used Your products for over 20 years in all my vehicles

Ive got Amsoil in everything from my 87 Bronco to my 06 Expy. Motor oil transmission fluid in both. My wife has the European oil in her Turbo Beetle and my mowers have the 4 stroke small engine oil. I use everything from zrod 20-50 to 5w -40 European turbo safe oil

I use this product and Amsoil 0W-30 in my vehicles. They are both great products.

The wear protection is phenomenonal, the performance improvements are noticeable and the extended drain intervals are what make Amsoil my favorite product. I currently run this oil in a half ton (V8) and SUV (V8) which put between 30000-40000 miles a year each.

after 1 year oil is in better shape in color and overall viscosity that conventional oil i use the recommended amsoil filter with cold winters and hot summers pulling a boat of 5000 saves me money only changing once a year instead of 3 with regular oil

I have been running Amsoil in my vechicles for over 10 years, now I am using 5 W 20 motor oil in my jk which I wheel often as well as daily drive, the oil is great and my vechicle appreciates it.

When I went to all synthetic products on the motor home the transmission stopped slipping and my mileage also improved.

I ran this oil on the 15,000 mile program because I'm on the gas pretty heavy at times. The first cycle went well, but the next cycle I pulled my trailer a lot and the oil was history at 6,000. Truck also had lifter tick at start up when motor was already at running temp. Went back to conventional oil and lifter tick was gone.

Your product have become overpriced and shipping prices are out of control, can't imagine if I wasn't A preferred paying customer...