i was driving home and all the sudden the truck kicked out of OD and the od light came on. I hooked up the scanner and started to check if there was a code and the trans temp was 130c or 266f. I checked my oil cooler lines and they were not cool. Removed check valve check valve from lines and it brought it to 115c or 239f while driving. i feel that is still too high The fluid, filter, and pressure regulators are new. So here is my question. What is the operating temp range and how do i get the temp to stay down.

 

Around 180 or so would be good..... up to about 230 is "ok".... but, fluid starts breaking down around that temp, and only gets worse as it gets hotter. Aux trans cooler, and maybe even an external filter (which gives a bit more fluid volume) will help. Of course, making sure the system is working as it should, should be your first step. (flush the cooler lines, NOT the transmission.)

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