I have noticed that when I am towing my huge and heavy trailer, my transmission never heats up - it doesn't really get warm hardly. It only goes up about 1/4 of the way up the guage - barely. This is even towing up hills.

Do you all have this experience?

Just talked to the local dealer's diesel tech about this same question.He told me that the Ally likes to run cool, and the trans gauge will only start to climb when pulling heavy and hard for extended periods. Sounds like yours is working properly.My $.02.

Sounds like you have a good Ally. Yes, the cooler they run, the better off it will be...

Just wait until my LLY friends see this . . . . Allisons behind the LLY tend to run somewhere between warm and hot.

Well, at least in warm weather, and I'm not about to suggest why :rolleyes: But then that's why Mike L. can sell them thar bigger transmission coolers.

Mine always seems to runs cooler in tow/haul.

When in tow/haul the torque convertor is locked, and less heat created b/c there is no slip.
My trans gets to about 140*-160*, no load, temp around 10* outside, winter cover on.

When in tow/haul the torque convertor is locked, and less heat created b/c there is no slip.
My trans gets to about 140*-160*, no load, temp around 10* outside, winter cover on.

It is my understanding, given the problem I encountered and subsequent discussions with Chevrolet and Allison, that the converter does not lock at low speeds — TH mode or not. Thus, on a long, steep, winding road with a heavy tow, especially in hot weather, where you can't get the speed up to over 25-30 mph because of the hairpin turns, you will overheat the Allison or come very close to it — running the stock cooler, trans pan and Dex. If kassl33 is not experiencing this under the same conditions, I would check the gauge for telling that which is not. The only other possibility is divine intervention, which most of us don't qualify for.

No, the guage works fine. When I was towing the load described at http://www.dieselplace.com/forum/showpost.php?p=2414866&postcount=7 the tranny temp went up to the middle at the 1/8 of a mile hill.

With all due respect, 1/8 mile is not a hill — try 8 miles with switch-backs at that grade. In fact, take I-84 (right there on your doorstep) and head east from Pendleton over the Cabbage Hill grade on one of those 100 degree Oregon days with that 12K # load and tell us what your trans temp gauge reads. Take your cell phone with you.

Cabbage "Emigrant" Hill is only a 6% grade. Not 8%. Also, 8% was a guess - but it is a HELL of a lot steeper than cabbage hill.

I do just fine on 6% grades with that weight.

It also does fine over the Siskiyou Summit and over the Grapevine.

Didn't say Cabbage Hill grade was 8%. It is officially billed as 6-7% and about 7 miles with sharp curves — so you can't really get your speed up and keep it up. Just suggested that you try it in hot weather with that 12K load and then read your trans temp gauge. Let us know when you do — because if you are able to keep your stock Allison cool, I want the formula. Or I'll talk about trading Allisons.

I hauled a 45' Sundowner from Madison Va to Louisville KY through the allegheny mnts. I'm not sure about the grades I think one was 6-7%, I was moving about 35mph at 3/4 throttle and the tranny never heated up excesivley It was about 75 degrees that day. I did pass a truck going 15 mph though. On the backside of the mnt the grade breaking came on and My tach hit 5k, thats when the transfer case went.

I lived in the Allegheny Mts. Lovely — but hills compared to the long, steep pulls in the Rockies. Too, I am told that above 25-30 mph, the converter locks up. So, as I indicated, my issue is below those speeds and in hot weather — 100 +/-. Others on DP have reported the very same problem with the Allisons — and it is acknowledged by Chevrolet and Allison. What is "excessively"? BTW, the manual indicates that the T/H mode grade braking will elevate the rpm but that it is safe! So your transfer case must be fine.

5k on the tac can't be good, 4k is high enough, imo. I'm guessing "excessive" might be when it pegs the red line in the temp guage.

yeah it heated up but no where near over heating, I was more worried about the tach hitting 5k than the tranny. I can't believe that would be normal.

I have got mine really hot pulling 15k in 100 degree heat. Needle completely in the red.

I changed the fluid after that because it smelled burnt as hell. Hope all is well in the old tranny.

One difference between those of you with '05's and newer is that you have more horse power and torque than '04 and lower (stock). Maybe they didn't upgrade the Ally when they did the motor and as a result, you are heating up more.

I have heard that the LB7's like I have just never had overheating problems.

Sorry to hijack thread but I didnt want to start another thread. Ive been city driving totally empty with about -2*C weather and my tranny is reading about 90*C is this normal? I just worry that when it warms up outside and Im hauling weight that its going to overheat...

Hmm, that is 194 degrees Fahrenheit. That is pretty hot. I am not sure, but that seems pretty high to me. You mentioned in another thread that you can burn out the tires at 40 mph. I think the previous owner did something and you are going to end up paying for it down the road if you don't settle that truck down.

Hmm, that is 194 degrees Fahrenheit. That is pretty hot. I am not sure, but that seems pretty high to me. You mentioned in another thread that you can burn out the tires at 40 mph. I think the previous owner did something and you are going to end up paying for it down the road if you don't settle that truck down.

Well it is only about 1/3 of the way up the gauge...no where near the red mark. I have been trying to get ahold of the previous owner but he is out of town.... on a good note if it does have a bunch of stuff done then less I will have to buy :D

When I posted that, I wasn't looking at how hot the temp gauge goes. Now I did look at mine and realized yours is warmer than mine, but probably not anything to worry about. Mine runs around 140 - 150 give or take.