AMSOIL products are formulated to keep trucks and equipment on the job longer and reduce maintenance costs

Signature Series Max-Duty Synthetic Diesel Oil

4x better wear protection*
AMSOIL Heavy-Duty Synthetic Diesel Oil  is engineered to provide 4X better wear protection than required by a leading engine manufacturer’s standard*, giving you the edge to keep trucks and equipment on the job longer.

  • Heavy-duty protection against wear
  • Reduced oil consumption
  • Excels in extreme temperatures

Diesel Oil

Engine Protection

A diesel truck is a serious investment – don’t skimp on protection. AMSOIL synthetic diesel oils provide the ultimate protection for your hard-working diesel engine, preserving the horsepower you crave and keeping you on the road.

Diesel for Commercial Applications

The AMSOIL CI-4+ synthetic diesel oil lineup provides additional high-quality options for pre-2007 diesel applications not equipped with diesel particulate filters (DPF).

  • Help control soot thickening, oxidation and wear
  • Control acids from combustion blow-by and exhaust gas recirculation
  • Extended drain intervals

Heavy-Duty Synthetic Diesel Oil

Top Grade Diesel Oil Protection for Trucks and Equipment

6X better wear protection*
Diesel Motor Oil / Engine Oil Formulated with top-grade synthetic technology and maximum additive fortification, Signature Series Max-Duty Synthetic Diesel Engine Oil provides 6X better wear protection than required by a leading engine manufacturer’s standard* – it’s protection boosted to the max.

  • Max-Duty protection against wear
  • Significantly exceeds industry requirements
  • Full specification coverage
  • Reduced oil consumption
  • Extended drain intervals

CI-4+ Synthetic Diesel Oils