Trans temps while towing

[Smitty]

Getting ready for the move to Florida and I'll be pulling the 56 on a trailer behind the Ford. Wondering where most trans temps are running while towing down the highway. The tow vehicle has the aux cooler and a deeper aluminum pan installed and I should be getting the remote trans filter, sending unit and gauge in the next couple of days.

I'll be coming back in a couple of weeks to get the Blazer and the boat. It's been pulling this boat for a few years so I'm not too worried about it.

 

[Muley]

I just put one in my dodge, and it gets a hair over 150, but I haven't had anything behind it, and I have yet to run it hard down the freeway for an extended period of time. I am heading to Cali on July 10th and plan on running it for about 5 hours before my first stop. I will have to see what hoovers at.

Enough about me, I have heard that 180 is about normal, but it never hurts to have a guage. I would get it all put in before you start your road trip, that way you will have a chance to get a baseline for it when the truck is empty and so forth.

Hope this helps some. /forums/images/graemlins/dunno.gif

 

[jarheadk5]

I've heard and read that 180deg is about as hot as ATF should get while in operation. After that, the additives start burning up and trans life jumps off a cliff...
If it gets hotter than that, I'd say ease up on it and let it cool a bit, or better yet take a piss-break.

My 2 cents...

 

[ZZ4x4]

On my HD with Allison which uses standard Dextron III ATF, the trans gets around 200 degrees in stop and go traffic. The red line on the factory gauge is at 270 degrees.

 

[84_Chevy_K10]

At 270 degrees your transmission is already gone.

I really don't think it should EVER under any circumstances exceed 220 degrees.

 

[ZZ4x4]

Tell it to GM. I'm just reading the gauge. /forums/images/graemlins/deal.gif
/forums/images/graemlins/whistling.gif

 

[Fubeca]

Here's a chart from one of the rebuilders -- I have no idea if its accurate:

 

[6.2Blazer]

It's probably accurate, but just remember that you would have to consistently run the trans at that particuliar temp. for it to fail at that mileage. There is a big difference between "short-term" and "long-term" temp. reading. Based on conversations with transmission engineers from one of the manufacturers, you can typically get a trans up around 250-275 degrees for very short durations without any drastic shortening of it's life. Much higher than that and you will start immediately damaging seals and such.

 

[miniwally]

My wifes 03 2500 HD with the 6.0 and 4L60E? gets to 175ish during normal driving during the summer. The guage from the factory has the red line at around 250. I would think that the GM enginerds must know something that we don't. I know that if I hadn't told my wife to watch that guage while towing and shut it down at around 225 she would run it all day just below redline. GM has to know this and think that it is fine for their trans to be that hot on a long term basis.
Like most other people that are not into cars she has the theory that if it is below that mark on the guage it must be fine.
I agree that trans temps should not be allowed to go much over 220 ever. I shut my buggy down if it creeps above 220. I have run for 20 min or so at 210 though.

 

[Smitty]

Let me take a different angle on this. If the transmission starts getting hot while driving down the highway, what is the best way to cool it down?

 

[jac6695]

That should have the 4L80E. I wonder where GM puts the sensor on the new trucks. My 4L80E gets much hotter towing, but I have the guage sensor in the hot line to the cooler. My brothers Allison rarely gets above the 200 degree mark, but the redline is up around 250-275.

 

[84_Chevy_K10]

[ QUOTE ]
Let me take a different angle on this. If the transmission starts getting hot while driving down the highway, what is the best way to cool it down?

[/ QUOTE ]

Pull over and stop and let it idle, it'll cool down.