Your concern was it was some how an issue for the pump to move the fluid back into the system and that would cause a problem. Again, how do it know?
42RLE getting hot
- Thread starter conlopez
- Start date
I overfill too, but it’s important to be aware how much fluid to add. The gears should be bathed in fluid but not submerged. Too much fluid and air bubbles will develop and cause issues with the hydraulics.
The 42RLE holds 8.8 qts and the service manual indicates adding roughly 4 qts when replacing the filter. If you add 4 and the transmission does not slip or flare, you’re probably good but could add 1/2-1 qt without any issues. Just make sure you’re not above the hot high mark on the dip stick when the transmission is at operating temp.
If you put in much more than 5 qts and notice weird shift behaviors, you probably added too much.
The 42RLE holds 8.8 qts and the service manual indicates adding roughly 4 qts when replacing the filter. If you add 4 and the transmission does not slip or flare, you’re probably good but could add 1/2-1 qt without any issues. Just make sure you’re not above the hot high mark on the dip stick when the transmission is at operating temp.
If you put in much more than 5 qts and notice weird shift behaviors, you probably added too much.
I took it back to the shop and they moved the oil cooler to the front. They zip tied it to the grille supports which is a interesting way to do it but whatever. It stays a little cooler now most of the time staying at around 185 if in heavy stop and go traffic on a 95+ day which still seems hot. But when I went off roading it got to 205. I have seen people say that going to 33's without re gearing can cause the 42RLE to get hot? I have 33' inch tires with the stock Rubicon 4.10's. Why is it getting so hot even with that oil cooler? I don't really want to buy and install that Derale one. Is it possible that the temperature sender is bad? Im getting the temp from the OBD port. After I get back on the road from being in the soft sand and mud there is a power loss that eventually comes back. Why would this be? The other problem is that they installed a 165 degree thermostat.
5.13s would help take some load off the trans as that is the rec ratio. It shouldn’t be running that hot though....
I have an outstanding transmission guy. I chatted with him extensively when I got my tow rig. I wanted to know how big of a cooler to install. He told me to install a gauge first and watch it. How hot should it get before I do something?
If you are towing, 230 sustained is fine.
It is common to see 200ish especially when you figure the coolant temp is running about the same. It will be hard to cool it below that and keep it there if you are working the trans hard. It also helps to know where the sender is. Where is the sender?
Im not sure where the sender is, im reading the temp it's giving me from the obd port
After reading Jerry B"s super detailed post about the Derale cooler, I installed one a few years ago.
My 05' TJ's 42 LRE with nearly 115,000 miles is still going strong.
But I did dump the Derail frame mount. It's good but too low for my preference. Instead, I opted for DIY fabbed underside body mount with 2" standoffs to bring the cooler above my tummy tuck and low enuf to catch air btwn the frame and 1" body lift.
I'm knocking on wood, but my 42LRE is still going strong. 33's and 4.56 gears.
Respectfully, the inline coolers are not as efficient as a radiator type.
My 05' TJ's 42 LRE with nearly 115,000 miles is still going strong.
But I did dump the Derail frame mount. It's good but too low for my preference. Instead, I opted for DIY fabbed underside body mount with 2" standoffs to bring the cooler above my tummy tuck and low enuf to catch air btwn the frame and 1" body lift.
I'm knocking on wood, but my 42LRE is still going strong. 33's and 4.56 gears.
Respectfully, the inline coolers are not as efficient as a radiator type.
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FYI, that’s not correct for the 05/06 models. OP’s numbers were valid.
The trans temp info is reported from my PCM on my 05 auto since the TCM is integrated with the PCM.
The 03/04 auto models have a stand alone TCM, so the trans temps are not communicated via the obd2 like they are for the 05/06 models.
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You spend your Saturday nights correcting posts nearly five years old?
You must lead an exciting life.
I corrected bad info so future readers aren’t harmed.
I’m not interested in your hard on, so kindly stop flirting with me.
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