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How can a 20W-50 be used in my transmission requiring a 75W-90?

How can a 20W-50 be used in my transmission requiring a 75W-90?

We get this question a lot and it’s a good one!  – How can a 20W-50 be used in my transmission requiring a 75W-90 (80W-90, 75W-110)

The answer is simple if you have a chart to reference by. The viscosity for engine oils and gear oils are not part of the same scale. In fact a SAE 90 gear oil may actually have less viscosity than a SAE50 (20W50). The illustration clearly explains why. Now you know something most mechanics don’t know.

See why motor oils sometimes work as transmission or gearcase lubes.

See why motor oils sometimes work as transmission or gear case lubes.

Note that when these charts were published when the 75W-110 category was not yet popular. A 110 make up that 1/3 section at the top of a 90WT and the lower part of the 140WT.

The AMSOIL 20W-50 will remain a 50WT engine oil through it’s recommended interval. Many other motorcycle oils have been tested to not follow this same path. They either fail after 1/2 their life or start at the low end of the category so are less likely to hold the needed viscosity. The higher the viscosity the more it costs the manufacturer so less $ to stock holders and AMSOIL has no stockholders to cheapen the formula!!

The new AMSOIL V-Twin Transmission fluid is right in the heart of the 75W-110 zone so use that product to really smooth out  your transmission if you have gear clatter.

Also note that if you take a bottle of each 75W-90 and 20W-50 you will notice they don’t flow the same – that’s because of their “W” or winter category. They will however when the temperature reaches the 100F as noted on the chart.

Here’s an updated clipping of the SAE Gear Oil segment to make better sense of the above.

75W-110 takes the old junction of the 90/140 split.

75W-110 takes the old junction of the 90/140 split.

New AMSOIL Motorcycle Primary and Transmission Fluid

V-Twin Synthetic Primary Fluid and Synthetic Transmission Fluid

Another new product for the Sioux Falls store based on years of requests. AMSOIL introduces both a Synthetic transmission fluid and a primary chaincase fluid.

While AMSOIL still recommends the original suggestion (MCV 20W-50 in all three) these satisfy those who want to use a specific fluid for the application. Comparing viscosities the new transmission fluid is similar to a 75W-110 gear oil in weight but has the same enhancements as our legendary motorcycle oils such as additives for storage and high RPM.  The Primary lube follows the line of the 10W-40 weights allowing for easier clutch and shifting performance.

V-Twin Synthetic Transmission Fluid promotes formation of a durable oil film on bearings and gears, helping to dampen loud thunks when shifting and reduce gear noise.

Motorcycle Transmission Fluid

AMSOIL V-Twin Synthetic Transmission Fluid is specifically designed for bikers who prefer a dedicated transmission fluid over a multi-use lubricant. Its frictional properties deliver smooth shifts and it helps quiet transmission noise, letting riders focus on enjoying the ride. V-Twin Synthetic Transmission Fluid is Warranty Secure™ and will not void your motorcycle’s warranty. It is a cost-effective, high-performance alternative to original equipment manufacturer (OEM) fluids.

Promotes Quiet Operation
V-Twin Synthetic Transmission Fluid promotes formation of a durable oil film on bearings and gears, helping to dampen loud thunks when shifting and reduce gear noise.

Protects Against Gear and Bearing Wear
Extreme pressures between gear teeth can shear inferior transmission fluids, reducing viscosity and compromising wear protection. AMSOIL V-Twin Synthetic Transmission Fluid resists viscosity loss due to shear and withstands extreme heat for excellent wear protection. Its robust molecules provide film strength to protect against damage from shock loading, while it contains extreme-pressure additives for additional protection against wear.

Delivers Smooth Shifts
V-Twin Synthetic Transmission Fluid’s finely tuned viscometrics and frictional properties provide smooth shifts, helping riders avoid missed shifts for crisp acceleration through each gear. It provides riders confidence that their transmission is going to respond as intended for an improved ride.

  • Protects against gear and bearing wear
  • Delivers smooth shifts
  • Helps eliminate loud thunks and gear noise

APPLICATIONS
Harley Davidson®, Triumph® and pre-2013 INDIAN® bikes.

    Delivers consistent clutch feel for confident takeoffs     Helps prevent clutch slip     Provides smooth acceleration     Helps riders easily find neutral     Protects compensator bearing, chain and gears against wear

Primary Chaincase Oil

AMSOIL V-Twin Synthetic Primary Fluid is purpose-built for bikers who prefer a dedicated primary chaincase lubricant. Its balanced formulation delivers consistent clutch feel for confident takeoffs, helping riders avoid killing the engine. It also protects components against wear to help riders get the most out of their bikes. V-Twin Synthetic Primary Fluid is Warranty Secure™ and will not void your motorcycle’s warranty. It is a cost-effective, high-performance alternative to original equipment manufacturer (OEM) fluids.

Delivers Consistent Clutch Feel & Smooth Acceleration
V-Twin Synthetic Primary Fluid is formulated with a balanced additive system that provides consistent clutch performance and feel. It helps riders easily find neutral and promotes smooth acceleration, whether in stop-and-go city conditions or when on the highway. Its superior load-holding capacity helps prevent clutch slip for confident takeoffs.

Protects Against Chain, Gear & Bearing Wear
V-Twin Synthetic Primary Fluid contains a heavy dose of anti-wear additives to protect the gears, chain and compensator bearing from premature wear. Its superior film strength helps protect against shock-loading, promoting reduced wear and longer component life.

Helps Reduce Operating Temperatures
In extreme heat, V-Twin Synthetic Primary Fluid’s thermally stable synthetic formulation naturally resists the harmful effects of thermal breakdown. It helps components stay cool and achieve optimum performance and life.

Maximizes Energy Efficiency
V-Twin Synthetic Primary Fluid’s balanced formulation reduces energy lost to drag in cold-temperature riding conditions. It promotes smooth shifts at startup and maximizes energy efficiency.

  • Delivers consistent clutch feel for confident takeoffs
  • Helps prevent clutch slip
  • Provides smooth acceleration
  • Helps riders easily find neutral
  • Protects compensator bearing, chain and gears against wear

APPLICATIONS
Harley Davidson®, Triumph® and pre-2013 INDIAN® bikes.

If you need to find out more about these products you can read more here and purchase if needed. Please call us at 800-579-0580 with specific questions.

Amsoil protects your warranty and adds one of its own

No issues with Warranty

New 20W-40 for Victory & Indian Motorcycles

A premium oil designed for those who demand the absolute best lubrication for their motorcycles. AMSOIL 20W-40
A premium oil designed for those who demand the absolute best lubrication for their motorcycles. AMSOIL 20W-40

AMSOIL 20W-40 V-Twin Motorcycle oil for Victory & Indian

New AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil (MVI) is formulated to provide premium protection for Victory and model-year 2013 and newer Indian motorcycles. It is the only full-synthetic 20W-40 motorcycle oil on the market, presenting riders a premium alternative to Indian- and Victory-branded semi-synthetic oils. Indian and Victory motorcycles incorporate a shared sump, and AMSOIL 20W-40 is formulated to provide outstanding protection for engines and transmissions. It is absolutely shear stable, keeping motorcycles well-protected even in extreme heat conditions.

 

AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil provides Indian and Victory riders with the confidence and security that comes with receiving maximum protection and performance for their bikes. It presents a premium alternative to higher-priced manufacturer-branded semi-synthetic oils.

Expect AMSOIL to always outperform. Seat of the pants tests too!

Expect AMSOIL to always outperform. Seat of the pants tests too!

Reduces Friction, Heat and Wear
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is engineered to protect critical components in high-heat conditions. It exceeds the standard for high-temperature film strength to deliver excellent wear protection (see graph) and contains a heavy treatment of anti-wear additives to reduce wear regardless of operating conditions. AMSOIL 20W-40 is thermally (heat) stable and contains maximum levels of oxidation-inhibitor additives. It is extremely resistant to breakdown and is engineered to prevent damaging sludge and carbon deposits for superior engine cleanliness.

Provides Anti-Wear Protection for Gears and Chains
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is shear stable and resists thinning from mechanical activity. It performs like a gear lube without the negative effects of extreme-pressure additives, such as poor wet-clutch performance.

Delivers Superior Rust Protection
Motorcycles are prone to rust from storage, humidity and short drives. Rust can cause major damage, such as uncontrolled wear, compression loss and blow-by. Good rust protection, however, comes by design and is not natural to motor oils. Unlike many motorcycle oils, AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil contains special anti-rust agents, providing outstanding protection against rust and corrosion.

Catalytic-Converter Compatible
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil meets the requirements for emission-system protection and is designed for use in motorcycles with catalytic converters.

Provides Excellent Wet-Clutch Performance
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil delivers the confidence of quiet, smooth shifting and positive clutch engagement. It controls heat and helps prevent slippage and glazing, while its high TBN helps improve clutch life by resisting the acids that can degrade clutch material.

APPLICATIONS
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is recommended for air- or liquid-cooled Indian, Victory and other four-stroke motorcycles calling for a 20W-40 motor oil. It meets API SM, JASO MA and API GL-1 specifications, providing outstanding protection for engines and transmissions.

COMPATIBILITY
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is compatible with other conventional and synthetic motor oils; however, mixing oils may shorten the oil’s life expectancy and reduce its performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed. Aftermarket oil additives are not recommended for use with AMSOIL Synthetic V-Twin Motorcycle Oil.

SERVICE LIFE
For on-road use in engines and transmissions, AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil and AMSOIL Ea® Motorcycle Oil Filters are capable of providing premium protection for up to 2X the motorcycle manufacturer-recommended change interval or one year, whichever comes first. Change other brand oil filters at standard intervals.

For off-road use in engines and transmissions, change AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil at the standard motorcycle manufacturer-recommended change interval.

For racing or in engines modified from the original factory design, no change interval recommendation is made; oil changes are at the owner’s discretion.

WARRANTY SECURE™
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is Warranty Secure, keeping your factory warranty intact. AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is a high-performance replacement for vehicle manufacturer-branded products and is also backed by the AMSOIL Limited Warranty. For details, visit www.amsoil.com/warrantysecure.