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So Many AMSOIL Motor Oils – How To Choose

How To Choose Between So Many AMSOIL Products

As we have come out with so many choices, these were designed based on customer and market requests.  The Signature Series remains the industry standard. Unlike the competition, Signature Series is constantly being evaluated as technology is made available. This is why it’s not API Certified because when you do that you are locked in to not changing formulations for extended periods. API certification actually holds back product improvements for example the dexos Gen 2, we already exceeded that years before it was required as every other minimum platform used to hold a certain quality level..

I like to explain our oils as: Signature Series – for those who want the most performance and unbeatable protection. Power to the wheels you can see the increase on a dyno (or feel seat of the pants). If you have a Turbocharged engine – it’s the only choice!!

The others offer industry leading protection for lower cost than on the shelf brands. All with a varying degree of additive balance. Shorter intervals but still saving you time!

The chart sums it all up!

Comparing Amsoil Products on a chart

Link for Full Size Chart

Of course the best resource are the individual product pages and the technical data sheets.

Your Manufacturer’s Warranty is Secure

Your Manufacturer’s Warranty is Secure and better protected with AMSOIL

AMSOIL lubricants maintain your factory vehicle and equipment warranties.

_by David Hilgendorf October 24, 2022

According to the Federal Trade Commission, manufacturers or sellers may make promises to stand behind the products you purchase. Any warranty offered must be available to read before purchase, so be sure to understand the details of what is covered before you buy.

Vehicle and equipment warranties often cover the expensive costs of labor and parts necessary to fix certain product defects or malfunctions within a predetermined amount of time or usage. It is important to know that your manufacturer’s warranty is secure for peace of mind.

Whether investing a few thousand dollars in lawn equipment, tens of thousands on powersports vehicles that may only be used a few months out of the year, or buying a new car or truck for daily use, manufacturers know these are big investments. They put a lot of focus on warranties to build consumer confidence and want you to buy their brand of parts and lubricants instead of aftermarket products.

Feeling pressured to use their products?

Some original equipment manufacturers (OEMs) falsely claim that you must use their brand of parts and lubricants or risk voiding your factory warranty. OEMs may even attempt to make you feel like they control what you can do with your vehicles. This is one of the biggest hurdles faced when recommending AMSOIL.

Thankfully, in America, the Magnuson Moss Warranty Act [15 USC Ch. 50 §2302(c)] protects your freedom to choose any brand of aftermarket parts and lubricants and your right to extend oil-change intervals beyond what is recommended in your owner’s manual, without voiding your warranty. Similar protections are available in Canada.

U.S. Federal law Protects you

Here are key points to remember for maintaining your factory warranty:

  • It is illegal to tie warranty coverage to the brand of parts or lubricants you use unless the manufacturer provides the parts or lubricants free of charge.
  • You have freedom to choose how to protect your vehicles and equipment, including extending recommended drain intervals.
  • Manufacturers can’t deny warranty coverage without proving an aftermarket part or lubricant caused a failure.

If anyone tries to tell you differently, contact the FTC at

Tips to avoid warranty issues

No one wants to file a warranty claim. It’s a hassle and can take months to resolve. Here are a few tips to help smooth the process should you ever need to use your factory warranty.

  • Read your warranty. Familiarizing yourself with what is and is not covered is worth your time.
  • Period of coverage. If your vehicle or equipment acts up, have it looked at before the end of the warranty term.
  • Service records and receipts. No matter who performs the service, providing proof that you maintained your vehicle removes the easiest way for manufacturers to shirk responsibility.
  • Speak up. If you think a service adviser denied your warranty claim unfairly, ask to speak with a supervisor. If the dealer does not resolve the issue, try another dealer, or contact the manufacturer. If you still aren’t getting results, contact your attorney general, local consumer protection office or the FTC.
  • Avoid aftermarket warranties. Many are scams. If a dealership is selling one please check the BBB looking up the company first! I can bet there are a lot of angry customers! If you think it’s legit remember it’s a contract and NOT a warranty so be sure to have them add in that you are going to use AMSOIL on your terms.

Strong products, strong warranty

AMSOIL designs high-performance replacements for manufacturer-branded lubricants that keep your factory warranty intact.

AMSOIL developed Warranty Secure branding to simply and effectively reinforce your right to use AMSOIL synthetic lubricants. We use clear, direct language to remind consumers that the law is on their side and to dispel fears generated by misleading or false warranty claims from any manufacturer, dealer or mechanic.

Because this issue is more prevalent in the powersports market, the Warranty Secure icon appears on all our powersports products, including AMSOIL Synthetic V-Twin Motorcycle Oil and ATV/UTV oils.

AMSOIL also offers its own Limited Warranty, offering an extra measure of protection. While some oil companies guarantee their products only for a specified mileage, we stand behind our products for as long as you use them.

Runs on Freedom™ Snowmobile Warranty

Additionally, AMSOIL offers the revolutionary Runs on Freedom Snowmobile Warranty offering complete peace of mind. Simply use AMSOIL INTERCEPTOR Synthetic 2-Stroke Oil exclusively in your new sled and we’ll cover any engine repairs for up to two years or 5,000 miles (8,000 km). Read the terms and conditions and register your sled today!

No other aftermarket snowmobile lubricant manufacturer offers this robust of a warranty. We’re so confident in our products, we’ll cover any repair to your snowmobile engine in the unlikely event of an engine failure. This means AMSOIL may end up fixing defective OEM parts that fail for reasons unrelated to our oil, but we’re more concerned about protecting our customers and their machines.

As millions of satisfied AMSOIL customers know, using AMSOIL synthetic lubricants or practicing extended drain intervals does not void vehicle or equipment warranties.

AMSOIL stands behind its products and the people who use them. If the OEM claims use of AMSOIL products violates the warranty, contact AMSOIL Technical Services (715-399-8324) or visit


Service Marine Lower Units to Prevent Water Damage

Service Marine Lower Units to Prevent Water Damage

Preventing rust and other water-related problems in marine lower units.

Most other Marine Gear Oils fail to make the grade. We learn more on that from our own customers when they make the switch.

_by David Hilgendorf April 24, 2023

Water and gear lube don’t mix. Unfortunately, you can’t avoid submerging your marine motor’s lower unit, and your boat isn’t going anywhere without the lower unit’s combination of gears, bearings and other components that turn horsepower into movement.

new ez pack for fuel saving marine gear lube


Water contamination – you can decrease the effects

Water contamination is bad for several reasons:

Viscosity loss – Viscosity measures a liquid’s resistance to flow or thickness. Your marine motor’s lower unit is designed to use a gear lube of a specific viscosity for optimal wear protection. Water can reduce the gear lube’s viscosity below what the manufacturer recommends, reducing wear protection.

Foam – A film of gear lube forms on the gear teeth it protects. This fluid film absorbs pressure and prevents metal-to-metal contact. Water contamination, however, invites the formation of foam. As the foam bubbles travel between gear teeth, they rupture under the intense pressure leaving nothing behind to prevent metal-to-metal contact, which leads to premature wear and potential gear damage.

Sludge – Water produces sludge, inhibiting heat transfer and increasing the lubricant temperature, which speeds chemical breakdown. The faster the lubricant breaks down, the sooner it fails to provide adequate protection, and the sooner it must be changed.

Rust formation – Water contamination invites rust formation on metal surfaces. Rust can flake off and circulate throughout the gear lube, where it acts like sandpaper and scours bearing and gear surfaces.


The solution is AMSOIL’s purpose built Marine Gear Lube

Avoiding contact with water is impossible when boating, so we’ve engineered AMSOIL Synthetic Marine Gear Lube to deliver advanced protection against power loss and gear wear, even with up to 15% water contamination.


So next time you are about to place your expensive outdoor boat guy sunglasses up on the bill of your ball cap ask yourself if you checked and replaced you lower gear unit’s oil this year!!

Good Day


How Often Should I Change Differential Fluid?

How Often Should I Change Differential Fluid?

Fluid change intervals depend on your vehicle, driving conditions and gear oil quality.

_by David Paiuilldorf | july 26, 2023

A differential is a set of gears that allows a vehicle’s driven wheels to revolve at different speeds when going around corners or over rough terrain. Those gears require lubrication, which is commonly called differential fluid, gear oil, or gear lube.

How often you should change differential fluid depends on your vehicle, driving conditions and fluid quality. If you drive primarily on the highway in temperate conditions and rarely tow or haul, you won’t need to change the differential fluid very often.

However, severe operating conditions break down differential fluid more quickly and place greater stress on the gears and bearings, inviting wear that reduces their lifespan.

Greater load capacity, less lubrication.

Truck manufacturer’s ongoing arms race for the highest towing capacity has resulted in trucks that place more stress on differentials than their predecessors. Meanwhile, differential fluid capacities have largely decreased or remained the same.

For example, compare a 1996 Ford F-250* Crew Cab to the 2021 version. Back in 1996, maximum towing capacity was 10,500 lbs. using a rear differential that held 3.75 quarts of gear oil. The 2021 model offers up to 15,200-lb. towing capacity using a rear differential that holds between 3.3 and 3.5 quarts of fluid.

This means less lubrication is responsible for protecting gears among higher heat and stress. In this environment, inferior lubricants can shear and permanently lose viscosity. Once sheared, the fluid film weakens, ruptures and allows metal-to-metal contact, eventually causing gear and bearing failure. That’s not good!

Increased temperatures in differential

As temperatures rise, lubricants lose viscosity and the extreme pressure between gears can shear the lubricant film, causing increased metal-to-metal contact, friction and heat. Friction and heat create a vicious cycle known as thermal runaway that spirals upward, leading to increased wear and potential gear failure.

Oh and let me tell you a quick story about AMSOIL diff fluid. Under thermal runaway the heat causes the gears or metal to expand just enough to act like a brake. We’ve had RVs comment on reaching 5 to 7 more miles per hour on mountain passes due to the reduction of heat using the AMSOIL Severe Gear. See what I’m saying?

Severe Service Differential Fluid Solution

If you drive via Severe Service towing conditions or haul heavy loads frequently, especially in warmer temperatures, most manufacturers recommend changing the differential fluid more often, sometimes as often as every 30,000 miles. This applies to most work trucks and anyone who pulls a camper, boat or trailer regularly

The best way to determine the recommended mileage interval for differential fluid changes is to check your owner’s manual. Use a high-quality synthetic gear oil to reduce gear wear and maximize your vehicle’s ability to tow and haul.

Amsoil’s Severe Gear Squeeze or Easy-Pack

Amsoil Squeeze Packs cut the differential oil change process in half!

AMSOIL SEVERE GEAR Synthetic Gear Lube is specifically designed for severe service. It maintains viscosity better than other gear lubes under rigorous use and contains advanced anti-wear additives for additional protection.

SEVERE GEAR often costs less than OEM-branded gear oil, and the AMSOIL Easy-Pack or I call Squeeze Pack eliminates the frustrations of changing gear oil. Its flexible design lets you easily reach inconvenient fill holes and squeeze all the gear lube out of the package. Less mess, less waste, less frustration.

And hey, by the way most auto parts stores don’t even carry a known name brand GL5 gear lube these days. Tell your auto parts store to PLEASE carry AMSOIL as it’s about the only real performance player out there and the only one that really works..



How To Fix Motorcycle Engine Pre-Detonation


How To Fix Motorcycle Engine Knock

Your bike can automatically detune its engine, but there’s an easy fix.

_by Eddie Hilgendorfen |May 10, 2023

Many modern motorcycles are designed to compensate for low-octane gasoline in an attempt to prevent motorcycle engine knocking. Unfortunately, the technology involved may also cause reduced performance, rough idle or lack of throttle response, making for a less than stellar ride experience. Fortunately, we can help you understand the root cause of this problem, and offer an inexpensive, quick and easy solution.

What is engine knocking?

Engine knock  or pre-detonation is caused by an improper detonation within the engine, which happens when fuel ignites outside of a timed ignition from the spark plug. In the race to improve fuel economy, modern high-performance engines have increased compression ratios, which also inherently increases the chance of pre-ignition detonation.

Octane measures gasoline performance against pre-ignition, detonation and the resulting engine knocking or pinging. The three most common octane ratings are:

  • Anti-Knock Index (AKI)
    The rating typically displayed on North American gas station pumps as the average of the fuel’s RON and MON octane ratings (R+M)/2.
  • Research Octane Number (RON)
    This rating is determined by testing fuel using a variable compression ratio under controlled conditions and is the most common industry rating worldwide. When comparing octane ratings, RON is typically higher than the AKI number, so an 87-octane AKI fuel at a typical gas station typically has a RON of 91-92. AMSOIL uses RON when conducting product validation and performance testing.
  • Motor Octane Number (MON)
    MON differs from RON testing by using a preheated fuel mixture, variable ignition timing and a higher engine speed to increase ignition stresses on the fuel. Though the tests are unrelated, MON results are typically 8 to 12 octane lower than RON.

Causes for loss of power and efficiency

Low-octane gasoline is more susceptible to uncontrolled and early ignition in the combustion chamber, so the higher the octane, the more compression the fuel can withstand before igniting. Pre-ignition robs the engine of power, can cause a noticeable knocking or pinging sound, and if left unchecked, can even cause catastrophic piston or cylinder damage.

This is why I decelerate (turning off the cruise control) when driving up or climbing steep hills and I also sometimes turn off the air conditioning. Also doing this you can see A decent increase in your fuel efficiency

High stress combined with lightweight design caused this dirt bike piston to fail. Dude was in first place so missed out on the cash prize.

Reduced performance.

Many modern motorcycle engines are equipped with a knock sensor. Pre-Detonation causes this sensor to adjust timing to compensating for low-octane gasoline. Unfortunately, adjusting the timing usually results in a noticeable decrease in performance, rough idling and lack of throttle response. When timing changes are done correctly, most riders shouldn’t even be aware that the performance has been reduced, but it’s easy to resolve this performance problem.

Boosting octane To Reduce Knock

The risk of engine knock can be reduced by:

  • retarding ignition timing
  • enriching the air-fuel ratio
  • reducing cylinder pressure or engine load
  • reducing the throttle or boost especially as you climb a hill
  • increasing the octane rating of the fuel
  • Engine work – lower compression

Therefore, the performance degradation caused by reduced engine timing can most easily be eliminated by increasing the fuel’s octane number. AMSOIL Motorcycle Octane Boost increases octane up to three numbers. On a bike that can be significant! This helps to eliminate motorcycle engine knocking and maximize power, performance and fuel efficiency. We get a LOT of feedback on this. Check out the product reviews.