AMSOIL 100% Synthetic Transmission Fluid

Product Details

AMSOIL 100% Synthetic V-Twin Transmission Fluid is a dedicated transmission lubricant engineered specifically for Harley-Davidson, Triumph, and pre-2013 Indian motorcycles with separate transmission sumps. It delivers smooth, confident shifts, quieter operation, and durable gear protection in a purpose-built formula that replaces OEM transmission fluids.

V-twin transmissions take a beating. The gear sets in a Harley-Davidson six-speed or a Triumph twin operate under extreme pressure, high heat, and constant shock loading from aggressive throttle inputs and heavy torque pulses. Running a generic multi-use lubricant in that environment often means clunky shifts, excessive gear noise, and accelerated wear on gear teeth and bearings. A dedicated synthetic transmission fluid, formulated specifically for the friction demands and viscometric needs of these transmissions, solves problems that multi-purpose oils simply cannot.

PROMOTES QUIET OPERATION
One of the most common complaints from V-twin riders is transmission whine and the hard "thunk" that comes with shifting through gears. AMSOIL Synthetic V-Twin Transmission Fluid forms a durable oil film on bearings and gears that dampens those loud mechanical noises. Its precisely tuned frictional properties reduce metal-to-metal contact noise at the gear mesh, so the transmission fades into the background and you hear more exhaust note, less drivetrain clatter.

DELIVERS SMOOTH, POSITIVE SHIFTS
Missed shifts and notchy gear engagement are more than annoying. They cost you acceleration and can leave you in an awkward spot in traffic. This fluid's finely tuned viscometrics and friction characteristics provide smooth, predictable engagement through every gear. Riders running Harley-Davidson Touring models, Softails, and Dynas commonly report a noticeable improvement in shift feel over the factory-fill Harley-Davidson Formula+ or SYN3 transmission fluid. The result is crisp acceleration without second-guessing whether the gear actually locked in.

FIGHTS GEAR AND BEARING WEAR
Extreme pressures between meshing gear teeth can shear inferior fluids, dropping their viscosity and leaving gears and bearings unprotected. AMSOIL Synthetic V-Twin Transmission Fluid resists viscosity loss due to mechanical shear and maintains film strength even under severe heat and load. In ASTM D4172 Four-Ball Wear testing at 40 kgf, 150 degrees Celsius, and 1800 rpm, this fluid produced a wear scar of just 0.55 mm, confirming strong anti-wear performance under extreme-pressure conditions. Its robust synthetic base oils combined with dedicated extreme-pressure additives protect against damage from shock loading during hard acceleration and aggressive downshifts.

THERMAL AND OXIDATIVE STABILITY
Air-cooled V-twin engines generate significant heat, and the transmission shares that thermal environment. This fluid posts a flash point of 228 degrees Celsius (442 degrees Fahrenheit) and a fire point of 242 degrees Celsius (468 degrees Fahrenheit), indicating excellent thermal stability. NOACK volatility testing (ASTM D5800) shows just 8.43% weight loss, meaning the fluid resists evaporation and burn-off at elevated temperatures. It also achieves a 0/0/0 result across all three sequences of ASTM D892 foam testing, so it will not aerate under the churning action of transmission gears, which would compromise film strength and shift quality.

COLD-WEATHER PERFORMANCE
With a pour point of -40 degrees Celsius (-40 degrees Fahrenheit), this fluid flows readily even in cold-morning startups or late-season riding. That means protection is in place from the moment you kick it into first gear, not five miles down the road after everything warms up.

SPECIFICATIONS AND COMPATIBILITY
AMSOIL Synthetic V-Twin Transmission Fluid is engineered for use in any V-twin motorcycle transmission that does not share a sump with the engine. This includes Harley-Davidson Big Twin models (Touring, Softail, Dyna), Triumph twins, and pre-2013 Indian motorcycles. It is a direct, high-performance replacement for OEM transmission fluids and is Warranty Secure, meaning it will not void your factory warranty. It is backed by the AMSOIL Limited Warranty.

SERVICE LIFE
AMSOIL recommends this fluid for up to 20,000 miles or one year, whichever comes first. That interval covers most riders for an entire season or more, reducing maintenance frequency compared to conventional OEM drain intervals.