Get the Best Heavy Duty Synthetic Diesel Oil for your Semi-Tractor Trailer, Big Rig, 16 or 18-wheeler Truck
AMSOIL synthetic technology delivers heavy-duty protection!
Heavy-Duty Engine Protection
Your semi deserves the best protection to prevent deterioration on rings and/or cylinder liners which will increase oil consumption, less compression, horsepower and fuel economy. Independent testing has demonstrated 4 times more protection which means less downtime and costly repairs.
Extreme Temperature Protection
Superior heat resistance compared to regular diesel oil. Also flows better in cold temperatures for easier startup while giving you maximum engine protection.
Minimize Oil Consumption
Our Max-Duty oil has less burn off which means less consumption while preventing vapors into the combustion chamber. Our oil is tough as nails!
Made in U.S.A.
We are proud of our synthetic oils which offer superior protection to vehicles, trucks, motorcycles, and boats. All Amsoil products are backed by a limited liability warranty. We are the first in synthetics, since 1972!
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Browse our line of diesel oils by weight
Our oils come in a 1 quart bottle, or for better discounts a 1 gallon jug, 2.5, 30, or 55 gallon drum, or 250 gallon tote!
Other viscosities available such as 5W-30, 5W-40, 0W-20, 10W-30, 15W-40, 0W-40, 10W-40, 15W-50, 20W-50, 5W-20 (Click below)
"Awesome diesel oil for my truck, always order, great cold starts just last time didn't get any cool stickers that I like so much, please send the stickers! :)"
"been using Amsoil diesel for 120 thousand miles already, even did an oil sample test and the results come back great, feel better using this synthetic for my Cummins 6.7L"
"engine sounds better when I use this, my Chevy truck must love it, will not be going back to the other brand I use to use, solid product with solid testing"