JKphotoshoot

I basically never use 4 hi. Except driving in the snow.
Lots of guys get the hot oil light running in 4 hi at moab last trip. I watch my tranny temps with the torque app and they do much better in 4 lo.
I run lots of sand dunes in sand hollow. Still use 4 lo. Tranny temps jump up fast in 4 hi and started dropping quick when in 4 lo.
I have the 2.72 case and can run 30 if needed. Dont know if thats bad for it but as far as I can tell its always helped my temps stay cool.
Seen to many overheat in 4 lo so im sticking to it.

Matthewd5

That's not normal

I'd bring it to your Jeep dealer or a local mechanic, preferably an off-road oriented one

Matthew

slangheld

Nobody has mentioned that the 07-11 auto tranny's will overheat in 4H unless going 25-30 mph. I bought an 09 auto, did a bunch of reading about beach driving. Saw a ton of experienced posts similar to what I have read here. Went to the beach, put it in 4H, and in 15-20 minutes got the dreaded "hot oil" light and chime. So, said a lot of bad words, and regeared my research towards specifically JKU auto's, sand, and hot oil. Recommendations are to install an auxiliary trans cooler first, air down to 15 psi (as a starting point) in deep sand, use 4L, and turn o/d off. You can even turn your a/c on to force the fan on. I haven't seen a post where anyone has overheated in 4L. Unfortunately the new design, computer control, and poorly sized and located cooler force your hand. None of the other stuff matters if you overheat and your rig burns to the ground. Sorry for the rant and post hi-jack. Just trying to pass along what I have learned.