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Allison Transmission TranSynd 668 Full Synthetic Trans Fluid

TranSynd1 - 12F
Shipping: Fluids Are Excluded From Free Ship Promotions and Can Only Ship UPS Ground.
Pricing: $48.00
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Allison Transmission TranSynd668 Allison Transmission TranSynd

This is the newest blend of full synthetic TranSynd fluid approved for Allison transmissions. TranSynd 668 has increased application coverage and an expanded additive package, effectively replacing the ever popular TranSynd1. This is the transmission oil your truck was born with!

Works in your 2001+ Allison LCT1000 5 or 6 Speed Automatic Transmission.


Castrol TranSynd 668 is a premium, full-synthetic automatic transmission fluid specifically formulated for Allison Transmission® on-highway automatic transmissions. TranSynd 668 provides oxidative stability, anti-wear performance, and friction durability, as well as TES 668™ specification differentiators such as extended anti-shudder durability and extended clutch friction durability. This fluid features an Allison TES 668 approval. The TES 668 spec is fully backwards compatible for TES 295® applications, but is not backwards compatible for TES 468™ applications.

Key Features 

  • 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
  • Recommended Applicator: Allison TES 668, Backwards Compatible with Allison TES 295

Keywords: Duramax Transmission Oil, Allison Transmission Fluid, Allison Transmission Oil

Operators Manual available in the Documents Tab for fluid recommendations, capacities and maintenance intervals.


Shipping Information

  • Item Requires Shipping
  • 8.0 lbs.
  • W9.0000” x H14.0000” x L12.0000”
  • Fluids Are Excluded From Free Ship Promotions and Can Only Ship UPS Ground.

Customer Reviews

Comment Total Reviews (1)

Awesome customer service
  • Currently 5/5 Stars

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Product ownership: Less than 1 week

Purchased from: Dirty Hooker Diesel

Fast shipping and Order packaged perfectly to avoid damage during shipping. Will be buying from DHD again!

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