Vendor : Mishimoto
Product Type : Transmission Coolers
Sku : MISMMTC-DMAX-20
Couldn't load pickup availability
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 |
We will be temporarily closed from Monday 10th August until Friday 21st August 2026 while we relocate to our new premises and carry out our annual stock take. Our website will remain open and you are welcome to place orders during this period. However, new orders placed between 11th and 21st August will not be processed or dispatched until we reopen. Please note: Any orders currently open and already in our system will continue to be processed as normal and will not be affected by the temporary closure. If you have an urgent order or require something that cannot wait until we reopen, please contact us via our website chat or email. We will do our best to assist wherever possible. Normal service will resume on Saturday 22nd August 2026. We apologise for any inconvenience this may cause and greatly appreciate your patience and continued support while we complete our relocation and annual stock take. Thank you for your understanding and continued support.
