Mobiltrans AST Series

Product Description

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.

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:

• 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 ExxonMobil for use in:

  • Heavy-duty transmissions, drivetrains, final drives and gear cases used in off-highway equipment

Specifications and Approvals

Mobiltrans AST meets or exceeds the requirments of the following industry and builder specification:
Caterpillar TO-4M

Typical Properties

Mobiltrans AST
SAE Grade
Viscosity, ASTM D 445
cSt @ 40ºC 107
cSt @ 100ºC 14.2
Viscosity Index, ASTM D 2270 134
Pour Point, ºC, ASTM D 97 -39
Flash Point, ºC, ASTM D 92 222
Density @ 15ºC kg/l, ASTM D 4052 0.882