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

  • Specially formulated for four-stroke powersports engines
  • Delivers quick startup protection
  • Helps prevent carbon/varnish formation
  • Easy cold-weather starts
  • Wet-clutch compatible
  • Anti-rust fortified for superior rust protection

Product Overview

Designed for top engine and transmission performance and ideal for equipment pushed hard on the trail or on the job. Anti-wear fortified and wet-clutch compatible. All-climate/all-season formula for excellent performance in both cold and hot temperature extremes. Use in ATVs, snowmobiles and other powersports applications that require 0W-30, 0W-40, 5W-30, 5W-40, 10W-30 or 10W-40 oil, including those made by Polaris,* Honda,* Yamaha,* BRP,* Can-Am,* Suzuki,* Kawasaki* and Arctic Cat.*

PROTECTS IN TEMPERATURE EXTREMES

  • Delivered exceptional protection against wear and deposits after 100 hours (3,421 miles [5,028 km]) of extreme dyno testing (see video).
  • Broad viscosity range and wax-free formulation make it excellent in both hot and cold temperature extremes.
  • Resists oxidation and oil vaporization to help prevent carbon/varnish formation, control oil consumption and minimize exhaust emissions.
  • 0W rating and -58°F (-50°C) pour point ensure easy cranking, excellent cold-weather starting and quick post-startup protection.

FIGHTS ENGINE & TRANSMISSION WEAR

  • Formulated with high levels of anti-wear additives that provide excellent protection for pistons, bearings and gears in transmission-containing units.
  • Shear-stable, SAE 40 viscosity delivers a thick lubricating film for an extra margin of protection in hard-working engines.
  • Premium synthetic base oils and additives resist chemical breakdown for long-lasting protection.

SPECIALIZED FOR POWERSPORTS

  • Contains robust dispersant/detergent additives that effectively neutralize acids and combustion byproducts prone to powersports engines.
  • Anti-rust fortified to protect components from rust during storage.
  • Controls foam common to high-rpm engines, promoting cooler engine operation and reduced wear.
  • Wet-clutch-compatible formulation helps prevent clutch slippage, helping deliver maximum torque and power to the wheels.

*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.

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Product information checked: September 2026. Product formulations, specifications, applications, availability and published claims can change.
For the latest official information, consult the AMSOIL Corproate Website.

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