What was done to your rig this week?

jeeeep

Hooked
Follow up to my post #23,393 transmission fluid change and PPE pan swap, needless to say it's a big disappointment and falls into the category of cold air intake.
It did nothing to bring down the temperatures of the transmission fluid.
The extra capacity might make the fluid last a little longer and the thicker pan may hold up better since I have no skid plate but, not something I want to test.
I would not recommend the upgrade as it did not provide the "marketing" benefits.
 

Breer

Caught the Bug
Follow up to my post #23,393 transmission fluid change and PPE pan swap, needless to say it's a big disappointment and falls into the category of cold air intake.
It did nothing to bring down the temperatures of the transmission fluid.
The extra capacity might make the fluid last a little longer and the thicker pan may hold up better since I have no skid plate but, not something I want to test.
I would not recommend the upgrade as it did not provide the "marketing" benefits.
Appreciate the honest review! Considered this after seeing your post as I'll be doing the fluid and filter change on mine in a couple months. Bought an oil extractor to remove the transmission fluid through the dip stick/fill. How did the rest of the fluid change go for you?
 

jeeeep

Hooked
Appreciate the honest review! Considered this after seeing your post as I'll be doing the fluid and filter change on mine in a couple months. Bought an oil extractor to remove the transmission fluid through the dip stick/fill. How did the rest of the fluid change go for you?
The JL does not have a dipstick and you can't really get something in the fill hole to siphon out the fluid because of the filter.
Overall, It's a simple job.
Be sure you have plenty of transmission fluid on hand and the Jeep is on level ground.
When you torque the pan bolts it recommends 10 ft lb,
I did one bolt at 10 ft lb and felt like it was going to snap or strip the bolt, thr rest I did at 9 ft lb, just covered 1100 miles and nothing is leaking.
Have a full can of brake clean fluid to clean out the pan, I used more than anticipated and ran out.
 

JimLee

Hooked
The JL does not have a dipstick and you can't really get something in the fill hole to siphon out the fluid because of the filter.
Overall, It's a simple job.
Be sure you have plenty of transmission fluid on hand and the Jeep is on level ground.
When you torque the pan bolts it recommends 10 ft lb,
I did one bolt at 10 ft lb and felt like it was going to snap or strip the bolt, thr rest I did at 9 ft lb, just covered 1100 miles and nothing is leaking.
Have a full can of brake clean fluid to clean out the pan, I used more than anticipated and ran out.
The JL also has two different systems that are actively working against any attempts to cool it more that the stock system.
"This thermostatic bypass valve’s function is to let the oil circulate through the cooler only when the oil has achieved a certain temperature. In most cases, it starts to slowly open at 75 degrees C (167 degrees F) and open completely at 90 degrees C (194 degrees F). This process helps the transmission get to operating temperature faster than if the oil ran through the cooler when cold."
And, there is a heat exchanger on the transmission that uses coolant to raise the temp of the transmission fluid.
People are trying to fight a transmission that is meant to run hot. I've had mine over 250 several times and it's not even in the yellow. I'll change my fluid and filter under "severe use" recommendations but running these transmissions in the low 200s isn't going to hurt them at all. I've read of people bypassing the heat exchanger, and maybe even the thermostatic valve, but if Jeep isn't even opening up the cooler fully until 194, it means they want the temp somewhere close to that for this transmission.
 

jeeeep

Hooked
The JL also has two different systems that are actively working against any attempts to cool it more that the stock system.
"This thermostatic bypass valve’s function is to let the oil circulate through the cooler only when the oil has achieved a certain temperature. In most cases, it starts to slowly open at 75 degrees C (167 degrees F) and open completely at 90 degrees C (194 degrees F). This process helps the transmission get to operating temperature faster than if the oil ran through the cooler when cold."
And, there is a heat exchanger on the transmission that uses coolant to raise the temp of the transmission fluid.
People are trying to fight a transmission that is meant to run hot. I've had mine over 250 several times and it's not even in the yellow. I'll change my fluid and filter under "severe use" recommendations but running these transmissions in the low 200s isn't going to hurt them at all. I've read of people bypassing the heat exchanger, and maybe even the thermostatic valve, but if Jeep isn't even opening up the cooler fully until 194, it means they want the temp somewhere close to that for this transmission.
Wish I would have done more research, would have saved me some change in replacing the pan.
good to know it's designed to run hotter but still not very comforting to see the temperature climb so high.
 

JimLee

Hooked
Wish I would have done more research, would have saved me some change in replacing the pan.
good to know it's designed to run hotter but still not very comforting to see the temperature climb so high.
I only found about the way it works when I was reading about how some 1350 double cardan driveshafts can come in contact with the heat exchanger down on the transmission. I don't think that increasing the fluid capacity is a bad idea and it may help slow down the temp rise. Believe me, the first time I looked and saw 256 I was worried. Good news is that because it is a sealed unit it takes a much higher temp than it normally would to boil the fluid.
 
I only found about the way it works when I was reading about how some 1350 double cardan driveshafts can come in contact with the heat exchanger down on the transmission. I don't think that increasing the fluid capacity is a bad idea and it may help slow down the temp rise. Believe me, the first time I looked and saw 256 I was worried. Good news is that because it is a sealed unit it takes a much higher temp than it normally would to boil the fluid.
Thanks for this information! We have some really steep grades around here and it’s very easy to hit 250 or more. Same as you, the first time I saw it I about panicked and was confused why the gauge wasn’t showing hot. I called my local dealer with concerns that I just screwed up and of course they were clueless. Since then I’m ok with the high temp but I will turn on Off Road Pages so I can monitor the temps in one spot… mainly just when towing though.
 

wayoflife

Administrator
Staff member
Thanks for this information! We have some really steep grades around here and it’s very easy to hit 250 or more. Same as you, the first time I saw it I about panicked and was confused why the gauge wasn’t showing hot. I called my local dealer with concerns that I just screwed up and of course they were clueless. Since I’m ok with the high temp but I will turn on Off Road Pages so I can monitor the temps in one spot… mainly just when towing though.
You ever have your trans get so hot that it starts to pull power? As in, you can't get up over 55 mph? If not, you're far from overheating it. 😁
 

wayoflife

Administrator
Staff member
Lmao! No, can’t say as I have! This happened on Jet or Jaws?
Yup - on both. Going up big grades at high speeds and in triple digit heat. In those conditions, your temp will get so hot, the engine/trans starts to pull power to cool things off. This by the way, is totally normal and designed to save your engine and trans. Oh, this also happens on diesel.
 
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Yup - on both. Going up big grades at high speeds and in triple digit heat. In those conditions, your temp will get so hot, the engine/trans starts to pull power to cool things off. This by the way, is totally normal and designed to save your engine and trans. Oh, this also happens on diesel.
That’s great info too, thanks! I know very little about the trans and just lived by “hot is bad”. Gives a little peace of mind that there’s a solid fail-safe built in to protect things under there.
 

wayoflife

Administrator
Staff member
That’s great info too, thanks! I know very little about the trans and just lived by “hot is bad”. Gives a little peace of mind that there’s a solid fail-safe built in to protect things under there.
I should note that on a stock Jeep, you should rarely if ever see this occur. As you know, we have really big tires, much higher gears, a LOT of weight and we were pushing it really really hard when it happened/happens to us. I talked to my Jeep engineer friends and the fail-safe is solid. It should not be a problem and so far, it hasn't been for us.
 
I should note that on a stock Jeep, you should rarely if ever see this occur. As you know, we have really big tires, much higher gears, a LOT of weight and we were pushing it really really hard when it happened/happens to us. I talked to my Jeep engineer friends and the fail-safe is solid. It should not be a problem and so far, it hasn't been for us.
Good to know as I’ll be testing this out when I tow my camp trailer to Montana to visit my daughter in a couple of weeks. 😂
 

JimLee

Hooked
I wish Tazer had a live function that let you set the fan to 100%, I'll turn up the radio, I want cooling. I never did the software update that changes the temp/fan curve, delaying any cooling is just foolish where I live
 

wayoflife

Administrator
Staff member
I wish Tazer had a live function that let you set the fan to 100%, I'll turn up the radio, I want cooling. I never did the software update that changes the temp/fan curve, delaying any cooling is just foolish where I live
Every fan has a duty cycle. If you ran it at 100% all the time, you would burn it out very quickly and then you'd have zero cooling.
 

JimLee

Hooked
Every fan has a duty cycle. If you ran it at 100% all the time, you would burn it out very quickly and then you'd have zero cooling.
Agreed. I should have quantified my statement a little better. I was thinking more like I know I have a big hill to climb and I want to run it at max for a set amount of time. I know the JL has a pretty good duty cycle, I've listened to that thing scream for hours at a time before.
 
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