Mishimoto 2020+ Chevrolet / GMC Duramax L5P 6.6L Transmission Cooler
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The factory transmission cooling on the 2020+ Chevrolet and GMC Duramax L5P 6.6L is sized for stock duty, and fluid temperatures climb fast under the sustained load of towing and heavy hauling. Heat is what wears a transmission out. The Mishimoto Transmission Cooler attacks the problem with raw capacity: a tube-and-fin core with a 245% increase in core volume over stock, giving the system far more headroom to keep fluid temperatures in a safe range when the truck is working hardest.----The core also adds a 137% increase in frontal area, putting more of the cooler directly in the incoming airstream, and a 173% increase in external fin area to move heat from the fluid into the air more efficiently. All-aluminum construction handles the thermal demands of stock and modified Duramax trucks alike, and the cooler retains the factory transmission line connections for a clean, complete upgrade with no additional adapters or plumbing.----Direct fit for the 2020+ Chevrolet and GMC Duramax L5P 6.6L. No drilling, cutting, or modification required. Backed by the Mishimoto Lifetime Warranty.
Installation InstructionsThis Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2021-2026 | Chevrolet | Silverado 2500 HD | Custom |
| 2020-2026 | Chevrolet | Silverado 2500 HD | High Country |
| 2020-2026 | Chevrolet | Silverado 2500 HD | LT |
| 2020-2026 | Chevrolet | Silverado 2500 HD | LTZ |
| 2020-2026 | Chevrolet | Silverado 2500 HD | WT |
| 2024-2026 | Chevrolet | Silverado 2500 HD | ZR2 |
| 2020-2026 | Chevrolet | Silverado 3500 HD | High Country |
| 2020-2026 | Chevrolet | Silverado 3500 HD | LT |
| 2020-2026 | Chevrolet | Silverado 3500 HD | LTZ |
| 2020-2026 | Chevrolet | Silverado 3500 HD | WT |
| 2020-2026 | GMC | Sierra 2500 HD | AT4 |
| 2024-2026 | GMC | Sierra 2500 HD | AT4X |
| 2020-2021 | GMC | Sierra 2500 HD | Base |
| 2020-2026 | GMC | Sierra 2500 HD | Denali |
| 2024-2026 | GMC | Sierra 2500 HD | Denali Ultimate |
| 2022-2026 | GMC | Sierra 2500 HD | Pro |
| 2020-2026 | GMC | Sierra 2500 HD | SLE |
| 2020-2026 | GMC | Sierra 2500 HD | SLT |
| 2020-2026 | GMC | Sierra 3500 HD | AT4 |
| 2020-2021 | GMC | Sierra 3500 HD | Base |
| 2020-2026 | GMC | Sierra 3500 HD | Denali |
| 2024-2026 | GMC | Sierra 3500 HD | Denali Ultimate |
| 2022-2026 | GMC | Sierra 3500 HD | Pro |
| 2020-2026 | GMC | Sierra 3500 HD | SLE |
| 2020-2026 | GMC | Sierra 3500 HD | SLT |