68RFE Transmission Cooler 2019-2024

This is a genuine Mopar transmission oil cooler, service part number 68322494AD, for 2019-2024 Ram 2500 and 3500 pickups with the 6.7L Cummins and the 68RFE automatic. It is a used unit, pulled from a 2024 Ram 2500 Tradesman with that same powertrain. Buy it if the cooler on your truck is leaking ATF, has been crushed or punctured by road debris, or is so plugged with debris from a failed transmission that flushing will not clear it.

What the transmission cooler does on a 68RFE truck

Every bit of heat the converter and clutches make ends up in the fluid, and the cooler is where it leaves the truck. Hot ATF leaves the transmission, runs forward through the cooler lines and a thermal bypass valve, crosses this front-mounted fin-and-tube core, and returns to the transmission. The 68RFE behind a Cummins sees a lot of heat when towing. ATRA's GEARS Magazine gives 200 degrees F as the ideal maximum fluid temperature. It says every 20 degrees above that roughly halves the transmission's expected life, so 240 degrees F leaves about a quarter of it. A cooler that leaks or flows too little shows up first as rising temperature on the gauge, then as burnt fluid and slipping clutches.

Symptoms of a failing or restricted cooler

• Transmission temperature climbing faster than normal on grades or while towing
• ATF drips or a wet, dirt-caked film on the cooler core, end tanks or line fittings
• A falling fluid level with no leak at the pan, case or lines
• Dark, burnt-smelling fluid shortly after a fluid service
• Fins crushed or tubes punctured from road debris or a front-end hit
• Lockup slip and overheating that keep coming back after a rebuild, from metal left in the old cooler

How to confirm the cooler is the problem

A cooler problem is a flow or leak problem, so measure before you replace anything. GEARS recommends checking flow with a flow meter or into a bucket at the return line, and looking for at least one gallon per minute. Low flow can come from the cooler, a kinked line, a stuck thermal bypass valve or a weak pump, so test each one. Our 68RFE pump failure guide covers the pump side. The Ram 2500 Cummins common problems guide covers overheating along with the other failures these trucks are known for. If a transmission has come apart and left metal in the fluid, a used cooler with fine passages is hard to clean fully. Replacing it protects the new or rebuilt unit.

Fitment

This cooler is for 2019, 2020, 2021, 2022, 2023 and 2024 Ram 2500 and 3500 trucks with the 6.7L Cummins and the 68RFE. Some 2019-up 3500s use the Aisin AS69RC automatic instead, so check which transmission your truck has. Production date and cooling package can change the part on a given truck. Before ordering, compare the number on your old cooler to 68322494AD, or send us your year and VIN and we will check it. The 68RFE parts collection lists other coolers for 2010-2018 trucks.

Install notes

• You get the cooler only. The end fittings and mounting tabs are attached as shown in the photos. Lines, clips and the bypass valve are not included.
• This is a used part. The fins show normal cosmetic wear, but no major fin damage was found. Flush it with clean ATF before installing, and look into both ports.
• Clean the line ends and check the O-rings or seals on the quick-connect fittings. Replace any that are flattened or cut.
• The thermal bypass valve sends fluid around the cooler until the fluid warms up. If it sticks, the truck overheats even with a good cooler. Many owners fit an open-flow 2019-2024 thermal bypass valve kit at the same time.
• Top off with ATF+4 and check the level hot, with the fluid at 160 degrees F or more. If the old cooler failed because of contamination, change the fluid and filters too; a 68RFE service kit with ATF+4 and filters covers it.

Is this a new or used cooler?

Used. It is a genuine Mopar cooler, part number 68322494AD, removed from a 2024 Ram 2500 Tradesman with the 6.7L Cummins and 68RFE. The fins show normal cosmetic wear and no major damage.

Will it fit my 2019 Ram 3500 Cummins?

It is listed for 2019-2024 Ram 2500 and 3500 with the 6.7L Cummins and the 68RFE. Some 3500s have the Aisin AS69RC instead, and cooling packages vary. Match 68322494AD to the number on your old cooler, or send us your VIN.

Does it come with lines or the thermal bypass valve?

No. You get the cooler core with its attached fittings and mounting tabs. Reuse your lines if they are in good shape, and inspect or replace the thermal bypass valve while you are in there.

Should I replace the cooler after a transmission failure?

If the old transmission left metal or clutch material in the fluid, yes, or at least flush the cooler and check the flow very carefully. Debris trapped in the cooler passages can wash back into a rebuilt unit and ruin it.

What fluid and how do I check the level?

Use ATF+4. After installing, run the truck until the transmission fluid is at least 160 degrees F, then check the level on the dipstick and top off. Recheck for leaks at both fittings after the first drive.

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