Trans temp on 48re...200* to hot?

[pwerwagn]

Just curious, just installed a trans temp guage on a 48re. We put it in teh hot line, before any heat exchangers.

It will get to 200* or so driving around town empty. Once on the highway it drops down lower, maybe 170*.

Its the first 48re I've had any experience with, and seems to run alittle hotter than all the 47's Ive messed with.



Is it normal?



thanks,

Jeff

 

[DWBauer]

pwerwagon,

I put a new set of gauges on my 2005 this summer in Las Vegas and was surprised to see the gauge occasionally go up to 210 driving around town. I started driving in Tow/Haul mode which locked up the converter and helped keep the transmission temperatures down. These high temperatures seem to be the normal when there isn't enough air flow through the transmisison cooler.

 

[Nate]

Sounds right in the hot line. I've hit 240-250* while backing a trailer without really forcing on the truck or anything.

 

[KLockliear]

In the hot line, 250 is your limit. 180-210 is about normal in town.

 

[pwerwagn]

Thanks for the response guys. I figured it was A-OK, just wanted to make sure.





thanks again,

Jeff

 

[Diesel Power]

i currently have mine in the pan and i see 180-200* normally

 

[Big P]

My transmission must be unusual. On the highway 100-115 degrees, around town 110-125 degrees. Probe is in the pan. Sounds low, but when the gauge says 100-110 degrees, I can hold my hand on the trans pan without even hurting it.

 

[BHolm]

My transmission must be unusual. On the highway 100-115 degrees, around town 110-125 degrees. Probe is in the pan. Sounds low, but when the gauge says 100-110 degrees, I can hold my hand on the trans pan without even hurting it.

I have mine in the hot line via a Mass Diesel transmission line. I have DiProcal gauge and it reads really low most of the time as well. Running down the highway fully warmed up it is between 130-160, on short trips it usually doesn't register above 100 I've seen it hit 180 backing a trailer around.

 

[LLTNT]

What temp. sets off the OEM trans light and busser ?

 

[brista]

I believe it is 275*. I read that in the manual somewhere.

 

[AMassaro]

I've hit 210 occasionally. That was on a 90+ degree day in slow city traffic. Most highway driving I see 176 degrees alot of the time. City, stop and go, 180-195. This is off of the Diablo Predator in data mode, which I believe gets the temp from the valve body location... Not sure though...

 

[pwerwagn]

What temp. sets off the OEM trans light and busser ?

On the 47re, our light came on at 270*.



--Jeff

 

[BHolm]

On the 47re, our light came on at 270*.



--Jeff

On my previous '03 QC, the light never came on, and the transmission cooked :{ That is why I have a transmission temp gauge now

 

[pwerwagn]

That sucks.

We had the light come on a few times before the trans guage, and figured it would be at a safe limit, 240 or so. Nope, ours came on at 270* according to the autometer trans temp guage...



--Jeff

 

[mpwalker]

Tanny Temp

I was going to ask the same question, my 2005, 48RE reached 256 the other day in Texas on a very hot 95 Degree temp day while pulling a heavy 5iver, it was only there for about 30 seconds and then cooled down to around 230 and ran that way for the next 20 or so miles as we crested some small hills running at 60 miles an hour with a head wind.



My temp gage is on the oil line from the transmission to the cooler, so not sure what the temp of the pan oil would be. One thing for sure is this transmission has run much hotter than any I have owned before but never has given me any problems and has 56,000 miles on it over half of it towing.



I change the transmission fluid every 25,000 miles and the fluid has always still been ok, (looks and smells good).



Have been thinking about putting on larger transmission pan and using synthethic transmission fluid because my experience has been that it handles the heat better, however is also has always seemed to run hotter than the standard fluid.



Anyone with experience in the synthethic with comments would be welcome

as want to learn what I can before investing the extra money.



Oh by the way, when backing my temp has always been higher than expected.



My son-in-law had a 2004. 5 and he told me his light would come on when back a small travel trailer up a small incline, but never had any transmission problems with it other that the light, which when it happen he always stopped and let it cool down and shifted to 4 wheel drive to finish the backing.



Thanks for the feedback.

 

[BHolm]

Alright... . So why is my gauge reading so low. There is no way we have a 100 degree difference in reality. I have the sensor in the Mass Diesel line. I assumed this was the hot line, clearly on my truck it isn't that hot. Could the line have been put in place of the return line? I was pretty sure it was a one way only deal, was I wrong?



I drove the truck up the mountain today, granted the temps were in the 40's and the truck empty but it wouldn't go over 160, convertor was almost never locked as the speeds are too slow. It is 13 miles of road that climbs over 3000 vertical feet. Should have been enough to generate some heat. Any ideas? The gauge is of little use if it is that inaccurate.