What is your transmission temperature

olfarmer,
Well Sir, it's not the same rig or, even transmission but, it may give you some form of reference. Ours is an '04 Itasca Horizon 36GD with the C-7, 330HP CAT engine and Allison 3000MH trans. During normal, flat ground, no-strain towing, in temps that hover around say, 65-86 degrees, that trans will sit at about 125-140 degrees, plus or minus a few.

But, if I start climbing a grade and, the outside temps start to rise to, oh, around say, 95 degrees, that trans temp will shoot to about 175-200, plus or minus. That rig never moves an inch without towing. We're presently towing a 5300 lb. 2011 GMC Sierra Extended Cab 4x4. And, sometimes it's got a 300 lb. lift/carrier in the back which, is carrying a 900 lb., GL 1800 Honda Goldwing.

So, that's what kind of load(s) is on ours and how it reacts in various towing situations.
Scott

Thanks Scott,
Quite a difference in rigs and you are towing a heavy load but it gives me some information.
Ed

My current '94 Foretravel w/Allison is pretty much right on with scotts.

But then my old '94 Allegro 454 TBI with the Chevy transmission was also close to that too. Could get it up to 150 once in a while. I actually wondered if it was working when I firsst hooked it up. And I was towing a Ford Focus. Depends lots on where your sensor is located. In general auto trannys don't run hot.

99 Ford V10 38 foot under 90 degree is around 125 and over 100 where it is most of the summer here is at 150. I only tow so can not give you any other readings.

You need to answer another question-- where are you measuring trans fluid temperature?

I have seen senders on line out to cooler, on return line and on some transmissions, on the transmission itself.

Reading will/should vary by location.

Thanks all for the replies so far. I am some what surprised at the cool temps you are getting as my 2014 Silverado with the 6 speed Allison was showing from 170 to 180 today not towing with outside temps in the low teens. I look forward to more comments about towing temps especially if anyone has the 4l80e.
Ed

06 Ford F53, rig weight is around 15,500 lbs., towing a 98 Honda Accord. Scan Gauge reports around 160 degrees normal driving. Never been east of the Mississippi so my only long pulls have been thru West Virginia, Maryland, Virginia and North Carolina.

Wolf 10, I don't know where the scan gauge temp is read from as it just reads the vehicles computer. The Silverado has a factory gauge. I would assume that the readings are taken where ever the manufacturer thinks is the most accurate place (probably internal).

Our Scan Gauge is around 150-160 on flat land towing. I've seen it as high as 220 climbing steep grades in 1st and 2nd. The gauge that is tapped into the test port is about 15-20 degrees cooler than what the Scan Gauge says.

I'm running Mobil 1 ATF.

From somewhere I seem to remember that the typical tranny is meant to run with a temp of at least 180 degrees by design. I measure pan temperature and run a pair of tranny coolers in front of the radiator and never see anything below 180. Climbing mountains I often times see 225 or more.

Edit: Here is a quote from a Haynes GM Transmission overhaul manual:

"Since normal engine coolant temperature is lower than normal transmission fluid temperature, the transmission fluid chamber transfers heat to the engine coolant, cooling the transmission fluid."

They are referring to the tranny fluid being routed through a "chamber" in the engine radiator. Now the thermostat in a typical engine is 195 degrees so by implication the tranny fluid must typically run higher than that to be receiving any cooling effect. And in fact the tranny fluid would get heated by the engine fluid up to that point.

I don't run my tranny fluid through the radiator since I avoid cold weather locations where it helps to warm up the tranny fluid on cold mornings.

Edit 2: From my GM P3 and P/G official 1994 Chassis manual the following is provided in chapter 7 for the 4L80-E transmission:

Transmission Fluid Checking Procedure:
"NOTICE: The automatic transmission fluid level must be checked with the vehicle at normal operating temperature 82 to 93 C (180 to 200 F)."

And a few pages back where they talk about and show the temp sensor inside the tranny:

"After the vehicle has been started, transmission temperature should rise steadily and stabilize between 90 and 115 celsius depending on load."

90 C = 194 F and 115 C = 239 F

So somewhere between what a lot of people are experiencing and what GM says the way things should be there seems to be a large gap. I'm quite comfortable with my tranny running above 180 and into the 200's all the time. But I run synthetic and change it out completely on a regular basis too.