Castrol TranSynd 668 has been specifically formulated for Allison Transmission on-highway automatic transmissions. This premium, full-synthetic fluid is Allison TES 668-approved and it builds on the demonstrated performance of the previous Allison TES 295 spec with key differentiators that include improved wear protection, extended anti-shudder durability, and extended clutch-friction durability. 

*TranSynd 668 is fully backwards compatible for both TES 295 and TES 468 applications.

* TES 668 is not approved for TC10.

• Delivers improved gear protection
• Delivers extended anti-shudder durability
• Delivers extended clutch-friction durability
• Allows for extended drain intervals of up to 300,000 miles or 48 months in general-duty transmissions and up to 150,000 miles or 48 months in severe-duty transmissions
• Provides excellent shear stability that provides a stable viscosity, which provides wear protection in gears throughout the drain interval
• Provides excellent thermal and oxidation stability resulting in lower deposit formation
• Provides superior high-low temperature performance due to full-synthetic base fluids
• Provides excellent corrosion and foaming resistance