Doomgaze
Well-Known Member
- Thread starter
- #1
2018 JLUR, all stock except 35" Nitto Ridge Grapplers.
During a normal drive, transmission temp will climb to 224-230. It's slow to heat up, and slower to cool down. Engine coolant temp averages 190-200, and will rapidly increase and decrease with RPM, seems normal for the coolant, but not so normal for the transmission.
Towing jetskis I seen the temp hit 237 degrees, I wasn't driving hard, I imagine if I were I could break 240 maybe even 250.
I was unware of these temps until after a 45 minute highway drive and the cooling fan came on full blast, that's when I started watching temps. I did some checking with a laser thermometer, and the transmission cooling lines are only slightly cooler than the trans temp, and as they get closer to the trans radiator they get a little cooler, 120ish, but then the radiator itself is cold, ambient air temp.
The dealer said there's a bypass, and that's why the radiator is cool. I'm assuming that at 230 degress, well over 3/4 the gauge, that the bypass should be off and the trans cooler should be engaged, but it's not. The dealer is unsure when/how the bypass works.
From what I've observed, the coolant fan will come on at full speed when the transmission temp breaks 224 degrees. At this point, engine coolant and all other temps are at normal levels, trans temp is the only thing higher than normal, so I'm assuming this is what's causing the fan to come on. It would seem then, that if the fan is coming on to cool the radiator, that the radiator then should be warm, but it is not.
Not sure my next step here. How do I convince the dealer to take a better look at the trans cooler? How do I get them to confirm the bypass is working?
Does anyone here happen to know what FCA considers optimal transmission temp? Does anyone know at what temperature the transmission cooler should start working?
Any other suggestions, thoughts? My worry isn't the max temp of 237, it's that once it reaches a high temp it does not cool down very well, it will take only drop 10 degrees in 30 minutes of idling, it really just doesn't feel like the jeep is doing anything to actively cool the transmission.
During a normal drive, transmission temp will climb to 224-230. It's slow to heat up, and slower to cool down. Engine coolant temp averages 190-200, and will rapidly increase and decrease with RPM, seems normal for the coolant, but not so normal for the transmission.
Towing jetskis I seen the temp hit 237 degrees, I wasn't driving hard, I imagine if I were I could break 240 maybe even 250.
I was unware of these temps until after a 45 minute highway drive and the cooling fan came on full blast, that's when I started watching temps. I did some checking with a laser thermometer, and the transmission cooling lines are only slightly cooler than the trans temp, and as they get closer to the trans radiator they get a little cooler, 120ish, but then the radiator itself is cold, ambient air temp.
The dealer said there's a bypass, and that's why the radiator is cool. I'm assuming that at 230 degress, well over 3/4 the gauge, that the bypass should be off and the trans cooler should be engaged, but it's not. The dealer is unsure when/how the bypass works.
From what I've observed, the coolant fan will come on at full speed when the transmission temp breaks 224 degrees. At this point, engine coolant and all other temps are at normal levels, trans temp is the only thing higher than normal, so I'm assuming this is what's causing the fan to come on. It would seem then, that if the fan is coming on to cool the radiator, that the radiator then should be warm, but it is not.
Not sure my next step here. How do I convince the dealer to take a better look at the trans cooler? How do I get them to confirm the bypass is working?
Does anyone here happen to know what FCA considers optimal transmission temp? Does anyone know at what temperature the transmission cooler should start working?
Any other suggestions, thoughts? My worry isn't the max temp of 237, it's that once it reaches a high temp it does not cool down very well, it will take only drop 10 degrees in 30 minutes of idling, it really just doesn't feel like the jeep is doing anything to actively cool the transmission.
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