AMSOIL Formula 4-Stroke® Powersports 0W-40 Synthetic Motor Oil

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AMSOIL Formula 4-Stroke Powersports 0W-40 Synthetic Motor Oil

AMSOIL Formula 4-Stroke Powersports 0W-40 Synthetic Motor Oil (AFF) is an SAE 40-weight synthetic built for four-stroke ATV, UTV, and snowmobile use, plus other four-stroke powersports applications that call for 0W-30, 0W-40, 5W-30, 5W-40, 10W-30, or 10W-40. The wax-free formulation pairs a 0W cold rating with high-temperature shear stability, and the wet-clutch-compatible additive package is friction-modifier free for shared sump engines that drive the crank and the gearbox from one fluid.

Wear protection in transmission-containing engines

Pistons, bearings, and gear teeth in shared-sump powersports engines see metal-to-metal loads that street oils never encounter. Formula 4-Stroke Powersports 0W-40 carries a Four-Ball Wear Test scar of 0.36 mm under ASTM D4172B (40 kg, 75 degrees C), and the SAE 40 high-temperature grade lays down a thick lubricating film for an extra margin of protection in hard-working engines. In an extended dyno protocol, the formula delivered exceptional protection against wear and deposits after 100 hours, equivalent to 3,421 miles (5,028 km) of accelerated severe service.

Cold cranking and post-startup flow

Sleds, plow rigs, and early-spring ATVs spend their hardest minutes during cold cranking, when an oil that will not flow leaves the bearings dry. Formula 4-Stroke Powersports 0W-40 holds a CCS viscosity of 5,805 cP at -35 degrees C (ASTM D5293) and a -50 degrees C (-58 degrees F) pour point under ASTM D97, so the pump can move oil to the top end on the first revolution at temperatures that defeat most powersports oils.

Heat resistance and oxidation control

Air-cooled twins, supercharged sleds, and turbocharged side-by-sides push sump temperatures past where conventional powersports oils oxidize, thicken, and varnish. The synthetic base oil chemistry holds a 234 degrees C (453 degrees F) flash point under ASTM D92 and a NOACK volatility of 7.8 percent weight loss under ASTM D5800, which restrains oil consumption and helps keep ring lands, valve trains, and turbo bearings clean. A kinematic viscosity of 14.8 cSt at 100 degrees C and a viscosity index of 179 (ASTM D445 and D2270) keep the oil thick enough to seal at operating temperature without thickening into a drag at start.

Wet-clutch compatibility for shared sump designs

ATV and four-stroke snowmobile designs that lubricate the engine and the wet clutch from a single sump need an oil that meets the JASO MA/MA2 and ISO-L-EMA2 frictional standards, otherwise plate slippage robs the wheels and track of torque. Formula 4-Stroke Powersports 0W-40 is friction-modifier free and meets JASO MA/MA2 and ISO-L-EMA2, so power transfer stays crisp under load on towing rigs, mud climbs, and high-horsepower trail use.

Detergency, acid neutralization, and storage protection

Powersports engines log short, hot, fuel-rich runs that load the oil with combustion acids and soot. A dispersant and detergent package supported by a Total Base Number of 9.1 neutralizes those acids and keeps deposit-forming residue suspended in the oil rather than baking onto pistons and ring lands. Anti-rust additives protect the camshaft, lifters, and bearing journals during off-season storage, important for sleds parked from spring through fall and ATVs that sit between hunting trips.

Anti-foam control for high-rpm running

Crankcase churning at high rpm beats air into the oil, and a foamy oil column collapses the lubricating film right when bearings need it most. The anti-foam treatment keeps the oil dense at high engine speeds, which improves heat transfer out of the bearings and slows wear in sustained wide-open running.

Recommended applications and service intervals

Use Formula 4-Stroke Powersports 0W-40 in transmissions and four-stroke engines in powersports applications that call for 0W-30, 0W-40, 5W-30, 5W-40, 10W-30, or 10W-40 and meet API SN, SM, SL/CF, SJ, SH, or SG, including units from Polaris, Honda, Yamaha, Ski-Doo, Can-Am (Bombardier), Suzuki, Kawasaki, and Arctic Cat. Match the oil change cadence to the equipment manufacturer's recommended drain interval for the service the machine actually sees.

• Normal trail, snow, and recreational use: change at the equipment manufacturer's recommended interval, listed in hours or miles in the owner's manual.
• Severe service such as racing, sustained wide-open throttle, deep mud, heavy towing, dusty trails, or fuel-injected snowmobiles run hard at altitude: shorten the drain interval to match the manufacturer's severe-service guidance.
• Two-stroke engines, separate-sump engines that specify a JASO FC/FD or API TC two-stroke oil, and engines that require a non-JASO MA fluid: not the right product, choose the appropriate AMSOIL two-stroke or specialty oil instead.
• Outside the United States and Canada: confirm the local AMSOIL or OEM viscosity recommendation against the equipment manual before switching grades.

Pair every change with a fresh AMSOIL or OEM-equivalent powersports oil filter sized for the engine. Mixing AMSOIL motor oil with another oil shortens the new oil's life expectancy and reduces its performance benefits, so a full drain at the change interval delivers the most value. Aftermarket oil additives are not recommended with AMSOIL synthetic motor oils.

Typical technical properties

Order AMSOIL Formula 4-Stroke Powersports 0W-40 Synthetic Motor Oil

Formula 4-Stroke Powersports 0W-40 ships in the AFFQT quart bottle (single each or case of twelve) and the AFF55 fifty-five gallon drum, and the formulation is backed by the AMSOIL Limited Warranty. For owners new to powersports synthetics, the AMSOIL vehicle lookup guide matches a specific ATV, UTV, or snowmobile to the right grade and filter, and the AMSOIL ATV oil guide walks through wet-clutch protection, shared sump designs, and the 0W-40 versus 10W-40 viscosity decision. Buy online

Frequently asked questions