Developed to protect the horsepower diesel enthusiasts crave and extend the life of hard-working commercial equipment in the most severe conditions. Signature Series synthetic technology delivers max-duty protection in on- and off-road applications.

MAXIMUM ENGINE PROTECTION

Delivers 6X more wear protection,¹ delivering extra protection so you can push your diesel with peace of mind

Provides long-lasting wear protection, keeping cylinder liners looking like new²

Delivers up to 60 percent better turbo cleanliness³

Withstands the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower

Provides up to 2X better rust protection⁴

¹Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation
²Based on independent testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
³Based on specification standards of CAT C13 2nd Ring Top Land Carbon testing
⁴Based on industry standard testing using the NMMA FC-W Rust Test.

DELIVERS MORE WEAR PROTECTION

Third-party testing shows Signature Series Max-Duty Synthetic Diesel Oil delivers 6X more protection against wear than required by Detroit Diesel’s* standard.^II

^IIBased on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation.
*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.

AMSOIL FIGHTS WEAR

AMSOIL delivers powerful engine protection. How good is it? In third-party testing compared to a leading brand, AMSOIL provided long-lasting wear protection, keeping cylinder liners looking like new.^DD

^DDBased on third-party testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
*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.

KEEPS TURBOS CLEAN

AMSOIL Signature Series Max-Duty Synthetic Diesel Oil provides protection boosted to the max, delivering up to 60% better turbo cleanliness^J and withstanding the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower.

^JBased on specification standards of CAT C13 2nd Ring Top Land Carbon testing

PROTECTS AGAINST RUST

Provides up to 2X better rust protection.^K

^KBased on industry standard testing using the NMMA FC-W Rust Test.

VISCOSITY CONTROL

Resists oxidation and the thickening effects of soot contamination

Retains viscosity after high-temperature service for maximum engine protection and efficiency

Provides up to 76 percent less oil consumption⁵

⁵Than required by the API CK-4 standard in the Caterpillar-1N oil consumption test

REDUCES OIL CONSUMPTION

Signature Series Max-Duty Synthetic Diesel Oil provides up to 76% less oil consumption.^L

^LThan required by the API CK-4 standard in the Caterpillar-1N oil consumption test.

EXCELS IN EXTREME TEMPERATURES

Provides outstanding protection and performance in hot and cold temperature extremes

Resists thermal (heat) breakdown better than conventional and competing synthetic diesel oils.

Stays fluid in sub-zero temperatures for easier starting, improved oil flow and reduced wear.