Towing increases transmission temperature?

[Jeep Junkie]

Guys, when I drive on steep Eastbound I-90 the Jeep shifts to as low as 5th gear to keep 75 mph pace, and transmission temperature also touches 200 degrees. And oil temperature to 224 degrees for a brief period. And my Jeep is tiny with rear seat removed and just 200 lbs me inside it. Now imagine a beefed up 4 door on 37's and towing 3,500 lbs behind it and also hauling a bunch of crap and some passengers. So how do the temperatures look like in that case? And unlike Gladiator we don't have a transmission cooler.

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[Jeep Wick]

Guys, when I drive on steep Eastbound I-90 the Jeep shifts to as low as 5th gear to keep 75 mph pace, and transmission temperature also touches 200 degrees. And oil temperature to 224 degrees for a brief period. And my Jeep is tiny with rear seat removed and just 200 lbs me inside it. Now imagine a beefed up 4 door on 37's and towing 3,500 lbs behind it and also hauling a bunch of crap and some passengers. So how do the temperatures look like in that case? And unlike Gladiator we don't have a transmission cooler.

Depends. I have the larger Gladiator grille inserts and 35's, but also 4.56 gears. Mine tows 3500 without issue. I checked temps intermittently but saw nothing notable. Are you sure there's not a transmission cooler? Pretty sure all the automatics have one.

 

[Jeep Junkie]

Depends. I have the larger Gladiator grille inserts and 35's, but also 4.56 gears. Mine tows 3500 without issue. I checked temps intermittently but saw nothing notable. Are you sure there's not a transmission cooler? Pretty sure all the automatics have one.

No, Wrangler doesn't have it

 

[Pape]

Guys, when I drive on steep Eastbound I-90 the Jeep shifts to as low as 5th gear to keep 75 mph pace, and transmission temperature also touches 200 degrees. And oil temperature to 224 degrees for a brief period. And my Jeep is tiny with rear seat removed and just 200 lbs me inside it. Now imagine a beefed up 4 door on 37's and towing 3,500 lbs behind it and also hauling a bunch of crap and some passengers. So how do the temperatures look like in that case? And unlike Gladiator we don't have a transmission cooler.

You have two choice:
1) you Understand the limitation of your rig and ease up.
2) you modify your rig to be able to meet your expectation.

BTW ~200F on the transmission is normal operating temperature on my side.

 

[grimmjeeper]

No, Wrangler doesn't have it

All vehicles with automatics have external transmission cooling. They have to because of the heat an automatic transmission generates. The problem is that you're working the engine and transmission harder when you tow. Harder work means more heat.

Most light duty vehicles just have a heat exchanger in the radiator. The transmission lines run from the transmission to the heat exchanger and back.

The gladiator adds an extra cooler on top of the one inside the radiator. They do that because they know how much more heat you generate when you tow.

It's possible to add an aftermarket cooler or just buy the parts they put in the gladiator and bolt it all in. It's a pretty straightforward job.

 

[Jeep Wick]

No, Wrangler doesn't have it

I see a water cooled 'transmission heater' and an actual cooler on the Mopar site. I will need to look at my Jeep when I get back to the office.

 

[flick2614]

I would say anyone on 37's towing at 75mph in a Jeep is likely exceeding the vehicles capability as well as all safety factors and deserves to overheat.

 

[6.2Blazer]

It has a transmission cooler built into the radiator. Not familiar with the Gladiator but they probably have an auxiliary cooler in addition to the one in the radiator.
Running up to 200F is pretty normal. This is because that is around the operating temp of the engine, which means the radiator will be at that temp. Since the trans cooler runs through the radiator you can't expect it to be any cooler than that when working hard.
As far as towing causing higher temps....as long as the cooling system has sufficient capacity you should get to a certain point and stay there (in this case right around 200 F). I would expect the factory design of the system to be able to tow the factory rated trailer weight under rather severe circumstances and stay within the safe operating range. If you actually start overheating either the cooling system is not working correctly or you are exceeding the towing ability designed by the factory.
The transmission downshifting and running in a lower gear does not cause it to overheat. Not really the way a trans works. You can actually be putting less stress on the transmission when it downshifts (it's not working as hard.....think of a multi-speed bicycle when you downshift gears when cycling up a hill. It's actually easier for you to pedal). You can also have less clutch slip and stress, and possibly have the converter locked up which again causes less heat).
Yes, simply towing is putting more stress on components. And when you have a big with oversize tires and more weight than stock there is additional stress on it also. But more stress doesn't mean too much stress. And it most circumstances the factory cooling system should provide sufficient ability to keep cool.

 

[GATORB8]

Guys, when I drive on steep Eastbound I-90 the Jeep shifts to as low as 5th gear to keep 75 mph pace, and transmission temperature also touches 200 degrees. And oil temperature to 224 degrees for a brief period. And my Jeep is tiny with rear seat removed and just 200 lbs me inside it. Now imagine a beefed up 4 door on 37's and towing 3,500 lbs behind it and also hauling a bunch of crap and some passengers. So how do the temperatures look like in that case? And unlike Gladiator we don't have a transmission cooler.

Worst I've done towing (~2500 lbs) with 37s is limp mode overheat the engine coolant. I-70 west through Kansas with a killer head wind, going 10 under the limit ambient temp of 114.

I've since learned to bank battery in the 4xe to prevent it. Well that and I tow the Jeep now, lol.

 

[patternman]

Guys, when I drive on steep Eastbound I-90 the Jeep shifts to as low as 5th gear to keep 75 mph pace, and transmission temperature also touches 200 degrees. And oil temperature to 224 degrees for a brief period. And my Jeep is tiny with rear seat removed and just 200 lbs me inside it. Now imagine a beefed up 4 door on 37's and towing 3,500 lbs behind it and also hauling a bunch of crap and some passengers. So how do the temperatures look like in that case? And unlike Gladiator we don't have a transmission cooler.

My Sport S equipped with tow package came with an external trans cooler.
I tow My Aliner approx 2800 pounds loaded. I installed a Mishimoto trans cooler to keep temps lower. The Mishimoto has approx 50% more volume, more surface area also.
I'm not affiliated with Mishimoto I was uneasy with the temps I was seeing.
I also installed an RpmExtreme Jeep JL - JT PWM Fan Controller. I,m very pleased with it.
I think it's been the most effective at keeping temps down.

 

[Jeep Wick]

So looking at the service manual, the 'transmission heater' is a heat exchanger that uses coolant to cool it. And then separately there is the trans oil cooler at the front. @Jeep Junkie I just confirmed my 22 has this, it's tucked in there exactly where this diagram shows. It is not 'built in to the radiator.' Mine did not come with tow package.

 

[Jeep Junkie]

So looking at the service manual, the 'transmission heater' is a heat exchanger that uses coolant to cool it. And then separately there is the trans oil cooler at the front. @Jeep Junkie I just confirmed my 22 has this, it's tucked in there exactly where this diagram shows. It is not 'built in to the radiator.' Mine did not come with tow package.

how do I confirm that mine also has it?

 

[roaniecowpony]

No, Wrangler doesn't have it

BS. My 2018 has two "coolers" for the 8 sp auto transmission.

 

[roaniecowpony]

how do I confirm that mine also has it?

On the same side as the front driveshaft, there is a coolant to ATF heat exchanger. Up in front of the condenser at the top, is a regular air-oil heat exchanger for the ATF.

 

[Jeep Junkie]

On the same side as the front driveshaft, there is a coolant to ATF heat exchanger. Up in front of the condenser at the top, is a regular air-oil heat exchanger for the ATF.

Will crawl under my Jeep tomorrow

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