The following is a compilation of common questions we have encountered while introducing AMSOIL's line of premium lubricants, fine filtration products and other car care products to individuals, companies using lubricants, and those who sell lubricants through various retail outlets.

This portion of our page is in development and will always be evolving, but if you have a concern or question that you would like to have answered or otherwise addressed, please do e-mail us so we can familiarize you with our products and also include your inquiry with our other listings of Frequently Asked Questions. If you have questions, chances are good others will be interested in learning also, so please do contribute!

    I was told that you should not put two different name brands of grease in wheel bearings. I have just replaced the bearings on my boat trailer and just want to make sure that I do not have to replace them again any time soon.

    Can you explain what the difference is between the Amsoil SAE 5W-30 SYNTHETIC MOTOR OIL and Synthetic XL-7500 5W-30 Motor Oil? The first one is slightly more expensive but has a recommended change interval of 25,000-miles/12-months, and the XL7500 mile oil has a shorter change interval of 7500-miles/6-months, but is there more to it then that?

    Why aren't all AMSOIL motor oils API licensed?

     How does AMSOIL INC. ensure their products meet or exceed the minimum specifications of the tests required for API licensing?

     I have heard motor oil base stocks refered to as Groups. What does this mean?

    What is the difference between a "micron rating" and a "beta ratio test" when referring to filters?

    Many of my performance minded prospects are using Redline oil. The current data sheets on our TRO do not include Redline in the Four-Ball Wear Test comparison. It used to be in the previous comparisons. Is there a reason Redline was dropped from the chart? How do the products compare today?

    I was told that AMSOIL Super Duty Oil Filters are inferior to "Wix (Napa) filters that costs half the price!" Is there any truth to this?

    An individual has posted a message on an Internet message board that said AMSOIL motor oils "lack sufficient EP additives" and the "quality of the product has dropped" in the last few years. Due to lack of EP additives and the drop in product quality he "wiped out bearings, pistons, rocker bushings, etc."

    Could you explain the statements I've heard about AMSOIL Universal ATF and Mercon and Mercon V Applications?

    I have a 2001 Ford F-350 Pickup with a Powerstroke Diesel with 7000 miles. I'm getting ready to change over to synthetic oil. What AMSOIL motor oil would you recommend to use?

    Can you explain the problems involving oil foaming and drivability problems in Ford/IH Diesel Engines?

    I just bought a new car, and I'ld like to try AMSOIL. Could using AMSOIL void my new car warranty?

    I was always told to change my oil every 3,000 miles if I wanted to keep my car running well. How is it possible to drive 25,000 miles without an oil change using AMSOIL, and will extending my oil change interval void my warranty?

    What is the "AMSOIL Product Warranty"?

    AMSOIL costs more than my regular oil does. How can I justify paying this higher cost?

    So the cost is not so high when you put a lot of miles on your car. But why should I use AMSOIL synthetic motor oils if I don't put a lot of miles on my car each year?

    I bought a new car a year ago, and I've been running petroleum motor oil in it ever since. Could switching to AMSOIL new cause mechanical problems?

    I've been using a petroleum motor oil since I started driving - that was a long time ago. Why should I switch to AMSOIL when I haven't had any problems with what I'm using?

    What is the Four Ball Wear Test? How good a predictor of engine wear is it?

    I've heard from several people, and even my local Harley-Davidson Motorcycle Dealer that using synthetic oil in my motorcycle is not a good idea as the roller bearings slide with synthetics instead of turning. What's the story?

    Will my oil pressure or idle rpm change when I switch to AMSOIL?

    Is there anything special I need to do before I switch to AMSOIL?

    What is the NOACK Volatility Test?

    I currently own a '91 4WD Suburban with 80K miles on it. The vehicle is currently using conventional oils (with no leaks) and I am interested in using your synthetics in the transmission and differential due to the extreme cold of our Alaskan winters. My previous experience in switching to a synthetic in another high mileage vehicle resulted in considerable seal leakeage. Would your products be any better at providing this tranisition (especially on high mileage vehicles such as mine) without leaks?

    I have driven diesels for as long as I've been driving. I am still hesitant in using AMSOIL mainly because I don't understand how an oil can CLEAN (or keep clean) a diesel engine if you don't change it regularly. Also, the main oil companies claim that synthetic oil left in too long will cause "deposits" in the upper cylynder or "rings" area.

    Could you please explain what the difference is between regular petroleum 10-30W and your synthetic 10-30W in cold winter conditions and advise which would be easyer to start my truck at -30C? The conditions where I live on some days is extreme and when I am at work I am unable to plug in the block heater on my engine.

    My son races motorcycles every weekend and I am searching for a high quality premix oil. What would you recommend?

    I just purchased a new Honda HS621 Single Stage Snowblower it has a 5.5HP 4 cycle Overhead Valve engine. The manual suggests using a "high detergent" SAE 5W-30 motor oil. Is there an AMSOIL product I could use and get the benifits of synthetic oil. Is AMSOIL detergent free?

    Recently a fellow approached me to help him with an oil consumption problem. His 100,000km Chev pick-up 350 V8 puffed on cold starts and started useing oil. I replaced all valve seals and found negligable guide wear ( almost new clearances ). What disturbed me was an abnormal amount of thick sludge build-up 1/8" thick coating the entire crankcase. When asked he told me he uses Amsoil and extends his change intervals as a result. Can you tell me what additives are present in your oils, and how many miles can these additives be expected to be active for. In the mean time I have prescribed stepped up changes useing Esso XD3-10W30 diesel grade oil for it's high level of detergent and Amsoil crankcase flush. Is there something I appear to be overlooking?

    I need to know how is Amsoil for an air cooled engine? I drive a VW (air cooled) and wondering if the cost of Amsoil is justified for my type of Motor?

    I am interested in finding out more about the AMSOIL By-pass oil filter. I am running a 7.3L PowerStroke Diesel in a Ford F250 series pickup. I truly believe this system might be the system for me but I need to know more about how it handles the soot buildup in a diesel engine. I am also interested in fuel filters. I have the internal injection system on my pickup (not the port injection) and it requires an element type filter. Do you carry such a thing and how much is it?