Unleash the full potential of your engine with Amsoil's superior 10W40 synthetic oils.
Shop NowHigh zinc. Good for flat tappet cams for gas or diesel engines. Lasts up to 25,000 miles or one-year.
Learn MoreBoost your engine's efficiency with top-notch lubrication.
Minimize wear and extend your engine's life.
Reduce emissions and save the environment with synthetic oils.
"Amsoil 10W40 is a game-changer for my car! The performance improvement is incredible."
"I use Amsoil for my truck, and it handles heavy loads like a breeze!"