Which Fluid Line to Use to Install Derale Transmission Cooler in 2000 Jeep Grand Cherokee

Question:

Question. 2000 4.7 Jeep. I want to install a secondary trans cooler and integrate it with the built in cooler in the radiator. How can I tell which line out from the trans is the high pressure line?

asked by: John C

Expert Reply:

When installing a supplementary transmission cooler you will want to install it in the system so it is downstream of the OEM cooler. This means you want to install it on the return line that runs from the OEM cooler back to the transmission; this will allow further cooling of the transmission fluid before it re-enters the transmission case.

You can find the return line by running the cold engine briefly, about 10-15 seconds or so, with the transmission in gear. Shut the engine off and check the lines' temperatures. The cooler one is the return line you want to use to install a unit like Derale # D13503.

expert reply by: Adam R