High transmission temperature while rock crawling!

[ZackDanger]

Just wondering if others are seeing this same thing. As we are cruising down the highway, the highest trans temps that I have seen is about 201 F. However, when rock crawling in 4-low or going slow over rough terrain in 1st gear (4-high), the temps get up to 214 degrees. I assume the high temps are due to a lack of airflow over the trans cooler. I also assume that 214 degrees is on the high side of normal. But it is interesting to me that the temps get so high when there is not a lot of strain on the transmission. Anyone else seeing this or have any thoughts on whether or not this behavior is normal?

Just because your ground speed isn’t fast doesn’t mean there isn’t strain on the transmission.

I don’t know what Ford considers “normal” operating temp, but nothing about what you’re describing worries me.

Sponsored

 

[Thed]

Like others said, it's normal. When you're crawling, you're putting the most strain on your torque converter. Trans fluid heats up quick when all you're doing is "slipping" the torque converter. All of your engine revolutions is basically being reduced to a few RPM using nothing but fluid coupling. That's a lot of friction, and a lot of friction means a lot of heat.

Generally you don't want to see your fluid temps touch 250*F. Coolant temps you want to keep under 220*F, again that's a general figure. Trans temp teetering at 220*F and coolant temp at 210*F on a hot day at low speeds is really pretty normal.

 

[flip]

 

[swami37]

It is under warranty..Drive it...If it is going to be an issue better to drive it now and find out before warranty ends

 

[goatman]

It is under warranty..Drive it...If it is going to be an issue better to drive it now and find out before warranty ends

Yeah, but you don't want to burn and degrade the fluid while under warranty, then the part fails after you're out of warranty. I get what you're saying. Good that the OP asked the question.

 

[Hopeless Diamond]

It would be interesting to know where they're taking the temp at, is it in the pan, or is it at the output of the torque converter which would be higher?

Very normal for higher temps while doing any offroading, slower speeds, less airflow, torque converter isn't going to lock up so it creates more heat. Simple solution, run it in 4Lo unless you're running at speed. 20-30 degree difference in my 3rd Gen 4Runner.

 

[dgorsett]

The TFL guys seemed unconcerned with temps in the 240's on the tow test. But good advise from Hopeless Diamond: don't hesitate to use 4L off road if speeds are going to stay low or you're climbing at low speeds. Nothing harder on an AT than prolonged torque converter slipping.

 

[Felix808]

Yeah, but you don't want to burn and degrade the fluid while under warranty, then the part fails after you're out of warranty. I get what you're saying. Good that the OP asked the question.

Yep & this would be deemed a maintenance item if it did fail & be on the owner even under warranty. The higher the temp the sooner the fluid must be changed out.
One more reason to add the PML trans pan. More oil capacity = more heat absorption before temp increase.

 

[jay-rod427]

Absolutely nothing wrong with 214. Modern transmissions are meant to run hotter than the days of old. As someone said converter slip is the single biggest source of heat in the trans system.

The trans literally has a thermostat that won't even let fluid circulate to the cooler until 190.

 

[vrtical]

those are not high temps for an A10.

 

[Superthornbird]

I dont worry about temps below 225° F

 

[MadMan4BamaNATL]

Hey guys, I”m reviving this very long dead thread because it’s an important topic and more Broncos are out, so good time to revisit the topic. It came up yesterday while out wheeling with a friend and forum member, so just putting out for everyone to be helpful.

If your Bronco is an auto transmission and you are off-roading, your transmission temp will increase if your speeds are lower than 30mph and the outside temp is maybe above 75f. What I mean is, the normal on road trans temps seem to be around 185f-195f.

Off-roading will see your trans temps climb above 200f and maybe towards 220+. In the old days of the 5 speed or 6 speed trans, this would be cause for worry, but not today. Why does this happen? That was covered earlier in this tread (good read), but basically, driving slow decreases air flow and cooling.

Bronco is a 10 speed of course, so those temps aren’t as big of a threat than years ago. What you don’t want is to get above 250f, which is when the trans fluid is likely to start boiling and you’ll smell it. You’ll smell it at 220, but not like 250f.

How to bring it down? Rest for 20-30 mins. This is common when off-roading and shouldn’t happen for 3-4 hours of wheeling with the car constantly moving.

What else can you do to keep temps down in the trans? Drive your AT in manual mode when in 4x4 drive (4H, 4L) and in a 10 speed, 2nd and 3rd gear (below 20mph) will be your friends.

What is difficult for me with this terrible guage cluster is knowing when to shift. Although hard to read, I‘ve tried shifting when revs in a gear get above 1.5 rpm. Not even sure if this is good, but it’s when the sound picks up for me and I have a 2.7. Things may be different for the 2.3; don’t have one so can’t speak to it.

Basically, play around with driving in manual mode and after maybe an hour, you should get the hang of it. Also, trans temp is in the selectable cluster to the right, either in the stack, or on its own, so you can watch the temp and how your shifts bring down the temps.

loose ground causes the trans to constantly shift to find the right gear. Without the air flow and cooling, all of this shifting likely heats things up. Manually shifting between 2-4 gears when again, below 30mph seems to bring temps down to the low 200f mark and out of my/our worry zone.

None of us know of the long term effects of the transmission at high temps, but if you get above 250f, basically whether or not a warning sounds, you need to get the fluid changed. Think this holds true even today, or at least I still would do so.

Any mechanics care to chime back in, please do?

 

[bluesun68]

I'm getting a burning smell while using engine breaking coming down hills, both at 60 and at lower speeds. Pretty sure it's transmission fluid, but not sure why this would happen.

 

[MadMan4BamaNATL]

I'm getting a burning smell while using engine breaking coming down hills, both at 60 and at lower speeds. Pretty sure it's transmission fluid, but not sure why this would happen.

Going downhill would make sense that the transmission would overheat a bit. Again, as long as the temp is below 250, shouldn’t be a bad worry. You don’t wait until it gets there either, so I’d say select the trans temp gauge when doing your mountain descents.

Assuming you’re in 2H. Aso, the manual suggests selecting your own gears when towing.

 

[Snacktime]

Pull your transmission dipstick and sniff it, smells burnt you have a problem. If its brown color then warranty it. Otherwise keep on going.

Unless your running dual temp gauges or pulling the sensor and benching it, your just looking at a number. It's a number and if it's always the same live with it. My last jeep had 3 water temperature gauges and the guy who bought it was like wtf. I had one in the engine block mid system, radiator inlet and radiator outlet. After a test drive in the middle of summer he bought it, he saw how one always hot and the other 2 said I bought to big of a radiator.

Sponsored