68RFE Thermal Bypass Valve Kit, 2019-2024 Ram 6.7 Cummins

This is the open-flow replacement for the thermal bypass valve that sits on the transmission cooler line ports of 2019-2024 Ram 2500 and 3500 trucks running the 6.7L Cummins behind either the 68RFE or the Aisin AS69RC. From the factory that valve holds fluid away from the cooler until the transmission comes up to temperature. It works fine when it is new. The problem is what happens after a few years of heat cycles: the thermostatic element sticks, flow to the cooler stays partially blocked, and the truck starts recirculating hot fluid back into the case exactly when it is towing and needs the cooler most.

The billet aluminum housing here has no thermostat in it. Cooler flow is open all the time, so fluid goes out to the cooler and back on every cycle regardless of temperature. Part number on the unit is ASP-CS21-00139004. O-rings are included. It bolts into the same location as the OE bypass valve and uses the same cooler line connections, so nothing has to be cut, re-routed, or adapted.

On the bench or in the driveway it is roughly a ten minute job with hand tools. Pull the cooler lines off the OE valve, unbolt the valve from the transmission, lube the new O-rings with clean ATF, set the billet housing in place, torque the bolts down evenly, and reconnect the lines. Check for weeping around the O-ring lands after the first heat cycle and top off the fluid. One more thing worth knowing: because the passage is open at room temperature, this also makes cooler line flushing far easier, which is the usual reason a shop pulls the OE valve off in the first place after a converter or transmission failure sends debris downstream.

Fits 2019-2024 Ram 2500 and Ram 3500 with the 6.7L Cummins and a 68RFE or Aisin AS69RC transmission. Verify your year, engine, and transmission before ordering, as the 2013-2018 trucks use a different bypass valve.