The Mishimoto 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, but its thermostat can fail closed — starving the cooler and overheating the transmission. This CNC-machined billet aluminum valve includes a fully serviceable thermostat for fast cold-climate warm-up, plus an installable thermostat-bypass insert for constant cooling in hot climates or heavy towing. Strategically machined internal passages improve flow over stock, and cooling fins machined into the body add heat dissipation. Black anodized, installs in under an hour.
| Type | Transmission thermal bypass valve kit (thermostatic) |
| Transmission | ZF 8HP |
| Material | CNC-machined billet aluminum, black anodized |
| Thermostat | Serviceable, with installable full-bypass insert |
| Install | Under 1 hour |
| Part Number | MMTC-WK2-TBV |
| 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) |
Shipping: In-stock orders placed before 3 PM EST ship the same day, and everything else ships within 24 hours. Standard, expedited, and overnight options are available at checkout. Backordered items ship as soon as we get them back in stock. Contact us for lead times. See the full Shipping Policy.
Returns: 30-day returns on new, unused items in original packaging. See the full Refund Policy.
