Mobiltrans AST

Extra High Performance Drivetrain Lubricant

Mobiltrans™ AST (All Season Transmission) is an extra high performance drivetrain lubricant engineered to meet or exceeds the requirements of Caterpillar's new TO-4M performance specifications for off-highway transmissions, drive trains, and hydraulic systems. This advanced technology lubricant provides clutch and brake compatibility and extended life that has not been possible with previous formulations. Mobiltrans AST incorporates a blend of semi-synthetic base oils with an advanced additive system. The product is recommended for all-season lubrication all drivetrain components in light to severe duty off-highway equipment operating in a wide range of environments.


Equipment lubricant recommendations

Our Mobil Serv℠ Product Selector tool will help you identify lubricant(s) for your specific equipment.

Data sheets

Features and Benefits

Today's technology has vastly improved the performance capabilities of heavy-duty off-highway equipment in terms of load, speed, control, and performance through innovative drivetrain designs. These designs have increased the requirements of drivetrain fluids to deliver higher performance, increased productivity, and reduced operating costs. For heavy-duty transmissions, friction control, wear protection, thermal stability, shear stability, rust and corrosion protection, and seal compatibility are features that must be optimally balanced to provide extended gear and synchroniser life, smooth shift control, fuel economy, and high load capability over a wide range of applications. Mobiltrans AST delivers exceptional performance in today's power train components including haul truck final drives with year-round application. The key benefits include:



Advantages and Potential Benefits

Excellent frictional properties

Optimum clutch friction retention and slippage control, excellent anti-chatter brake performance, and extended clutch/brake life

Excellent load carrying, anti-wear, and EP performance

Greater wear protection, extended component life, and reduced cost of operation

Outstanding protection against deposit formation

Longer seal life, extended drain, and service intervals

Maximum protection from corrosion of copper and its alloys

Protects and extends the life of synchronizers

Optimized thermal and oxidation protection

Extended transmissions and drive train life

Exceptional shear stability

Maintains effective viscosity and film strength during severe operation

Outstanding low-temperature fluidity and pumpability

Smoother shifting with quicker starts and reduced wear

All-season capability

Extended drain and service intervals with lower operating costs and higher productivity



Recommended by Imperial Oil for use in:

     •  Heavy-duty transmissions, drivetrains, hydraulic systems in off-highway equipment


Specifications and Approvals


This product is recommended by Imperial Oil for use in applications requiring:

Allison C-4

KOMATSU KES 07.868.1


This product meets or exceeds the requirements of the following industry and builder specifications:

Caterpillar TO-4M


Properties and Specifications



Brookfield Viscosity @ -30 C, mPa.s, ASTM D2983

45,000 @ 30ºC

Density @ 15 C, kg/m3, ASTM D4052


Flash Point, Cleveland Open Cup, °C, ASTM D92


Kinematic Viscosity @ 100 C, mm2/s, ASTM D445


Kinematic Viscosity @ 40 C, mm2/s, ASTM D445


Mini-Rotary Viscometer, Apparent Viscosity, -30 C, mPa.s, ASTM D4684

37,000 @ -30ºC

Pour Point, °C, ASTM D97


Viscosity Index, ASTM D2270



Health and safety

Health and Safety recommendations for this product can be found on the Material Safety Data Sheet (MSDS) @