The Mishimoto full-flow thermal bypass valve kit replaces the failure-prone factory bypass valve on the ZF 8HP transmission in the Jeep Grand Cherokee, Grand Cherokee L, and Dodge Durango. The stock valve withholds transmission fluid from the cooler until operating temperature, and its thermostat can fail closed — starving the cooler and overheating the transmission. This all-aluminum CNC-machined full-flow valve eliminates the thermostat entirely, pumping fluid through the cooler the moment the vehicle starts for constant cooling. The full-flow design is ideal for hot climates, extreme driving, or heavy towing. Backed by the Mishimoto Lifetime Warranty.
| Brand | Mishimoto |
| Type | Full-flow transmission thermal bypass valve kit |
| Transmission | ZF 8HP |
| Material | CNC-machined billet aluminum |
| Function | Full-flow (no thermostat); constant cooler flow |
| Best for | Hot climates, towing, extreme driving |
| Warranty | Mishimoto Lifetime Warranty |
This part fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2018-2024 | Dodge | Durango | Citadel / GT / R/T / SRT / SRT 392 (all trims) |
| 2016-2020 | Jeep | Grand Cherokee | Laredo / Limited / Overland / Summit / SRT / Trailhawk (all trims) |
| 2018-2021 | Jeep | Grand Cherokee | Trackhawk / High Altitude / Limited X |
| 2021 | Jeep | Grand Cherokee L | Laredo / Limited / Overland / Summit (all trims) |
