AMSOIL SIGNATURE SERIES 0W-40 100% SYNTHETIC MAX-DUTY DIESEL OIL

AMSOIL Signature Series 0W-40 100% Synthetic Max-Duty Diesel Oil delivers maximum-duty wear protection, viscosity stability, and extended drain capability for diesel engines operating in the most punishing conditions. Built on top-tier synthetic base oils and a robust additive package, this is the oil you reach for when your diesel works harder than the factory ever planned.

Modern diesel engines produce more power, more heat, and more soot than ever before. Turbocharged pickups towing heavy loads, Class 8 trucks running cross-country, and off-road equipment grinding through 12-hour shifts all push oil beyond its design limits. Add in extreme cold starts, high exhaust gas temperatures from EGR systems, and the carbon contamination that comes with diesel combustion, and you have a recipe for accelerated wear, viscosity breakdown, and turbo deposits. A 0W-40 synthetic diesel oil needs to handle all of it without flinching.

6X MORE WEAR PROTECTION FOR CYLINDER LINERS AND RINGS
Cylinder liner scuffing is one of the fastest paths to lost compression, increased oil consumption, and reduced horsepower. In third-party testing using the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222, AMSOIL Signature Series Max-Duty delivered 6X more wear protection than required by the test standard. The result was a non-scuffed liner that looked virtually new, while a leading conventional 15W-40 diesel oil produced severe scuffing under identical conditions. For Duramax, Cummins, and Power Stroke owners pushing their trucks hard, that level of liner protection translates directly to longer engine life.

UP TO 60% BETTER TURBO CLEANLINESS
Carbon deposits on turbo components restrict airflow and reduce boost efficiency. Over time, coking on the turbine housing and center section can lead to bearing failure. AMSOIL Signature Series Max-Duty delivers up to 60% better turbo cleanliness based on the specification standards of the CAT C13 2nd Ring Top Land Carbon test. That matters when you are pulling a fifth wheel up a mountain grade or running a tuned diesel that is producing boost pressures well beyond stock calibration.

OUTSTANDING VISCOSITY CONTROL AND SOOT MANAGEMENT
Diesel combustion generates soot, and soot causes oil to thicken. Thickened oil circulates poorly, starves bearings of lubrication, and increases fuel consumption. Signature Series Max-Duty uses top-tier synthetic base oils that are naturally resistant to oxidation and soot-induced viscosity increase. Boosted detergent and dispersant additives keep soot particles suspended independently, preventing them from agglomerating into larger, wear-causing particles. The 0W-40 grade (DZF) posts a viscosity index of 180 per ASTM D2270, confirming its ability to maintain a stable viscosity profile across a wide temperature range.

4X BETTER COLD-TEMPERATURE PERFORMANCE
Cold starts are where a huge percentage of engine wear occurs. Thick oil that struggles to flow leaves bearings, cylinder walls, and turbo components unprotected during the critical first seconds after ignition. AMSOIL Signature Series 0W-40 delivers 4X better cold-temperature performance compared to SAE 15W-40 oil in the ASTM D5293 Cold Cranking Viscosity test. The DZF formulation posts a CCS viscosity of 5,776 cP at -35°C. Unlike conventional oils, it contains no wax, staying fluid in sub-zero temperatures for faster oil pressure buildup and reduced dry-start wear. For anyone running a diesel in northern climates, from Minnesota to Alberta, the 0W-40 grade provides a meaningful cold-flow advantage over thicker viscosities.

MINIMIZES OIL CONSUMPTION
Volatile base oils burn off in high-temperature service, reducing oil levels between changes and increasing emissions. AMSOIL Signature Series Max-Duty provides up to 76% less oil consumption than required by the API CK-4 standard in the Caterpillar-1N oil consumption test. The 0W-40 grade records a NOACK volatility of 10.9% weight loss per ASTM D5800. Lower volatility means less oil vapor entering the combustion chamber and less need to top off between drain intervals.

UP TO 2X BETTER RUST PROTECTION
Diesel engines that sit idle between jobs, or that operate in humid and coastal environments, are vulnerable to internal corrosion. AMSOIL Signature Series Max-Duty provides up to 2X better rust protection based on industry standard testing using the NMMA FC-W Rust Test. In the published comparison, AMSOIL significantly outperformed Shell Rotella T4, Mobil Delvac Super 1300, Schaeffers Durability, and Lucas Magnum 15W-40 oils in the same test protocol.

SPECIFICATIONS AND COMPATIBILITY
AMSOIL Signature Series 0W-40 Max-Duty Synthetic Diesel Oil meets or exceeds the following specifications:

API CK-4/SN, CJ-4, CI-4+, CF, CF-2 / Volvo VDS4.5, VDS4, VDS3 / Mack EOS-4.5, EO-O / Renault RLD-4, RLD-3 / Cummins CES20086, CES20081 / Caterpillar ECF-2, ECF-3, ECF-1-a / DDC 93K218, 93K215, 93K214 / ACEA E9, E7 / MB 228.31 / MAN 3575 / MTU Type 2.1, II, I / JASO DH-2 / Deutz DQC III-10LA / Scania LA-2 / Chrysler MS 10902 / Ford WSS-M2C171-F1

It is also compatible with conventional and synthetic engine oils. Mixing with other oils will shorten life expectancy and reduce performance benefits. Aftermarket oil additives are not recommended.

SERVICE LIFE
Heavy-Duty On-/Off-Road: Three times (3X) OEM-recommended drain intervals, not to exceed 60,000 miles, 600 hours, or one year, whichever comes first.

Turbodiesel Pickup: Two times (2X) OEM-recommended drain intervals, not to exceed 25,000 miles or one year, whichever comes first.

Gasoline Engine: Two times (2X) OEM-recommended drain intervals, not to exceed 15,000 miles or one year, whichever comes first.

Competition Use: Provides lasting protection for multiple events. Use oil analysis to determine appropriate drain intervals.

Extended drain intervals are not recommended for performance-modified engines or when using biofuels containing more than 10% ethanol or 15% biodiesel (B15). Drain intervals may be extended further with oil analysis.

Property	0W-40 (DZF)	Test Method
Kinematic Viscosity @ 100°C, cSt	15.7	ASTM D445
Kinematic Viscosity @ 40°C, cSt	92.8	ASTM D445
Viscosity Index	180	ASTM D2270
CCS Viscosity @ °C, cP	5,776 (-35)	ASTM D5293
Pour Point, °C (°F)	-48 (-54)	ASTM D97
Four-Ball Wear Test, Scar, mm	0.47	ASTM D4172
NOACK Volatility, % weight loss (g/100g)	10.9	ASTM D5800
Total Base Number	10.1	ASTM D2896
High-Temperature/High-Shear Viscosity, cP	4.2	ASTM D5481
Sulfated Ash Content, wt. %	0.99	—