JohnDeere

Just got back from camping in Pitkin CO and had some questions about tranny temps.... I have a 2009 1500 2WD Crewcab. It has the 6 speed tranny. I was pulling a 15' pop up camper and I also had the pickup loaded down pretty good. Going over Monark Pass, which is 11,500', I kept it at around 40 mph. I had my "tow haul" on. It would not pull it in 3rd at that mph so I was back in 2nd most of the time. My tranny temp got all the way to 225 degrees. I got scared and stopped to let it cool down a little. Ok.... coming back over a few days later I kept it at 20 mph with "tow haul" on. I still warmed it up to 223 degrees. Is this normal? Monark Pass is around 6 miles of 6% grade going west and around 7 miles of 6% grade going east. As far as just "going down the road" pulling my pop up, my tranny temp runs around 174 to 180. Just wondering where I'm at with the tranny temps..... Thanks for any and all help!!!

Allan In NE

Totally normal.

At around 270° you would want to find a pull out, as they unravel at 305°.

The kindest thing you can do for your truck is to mount a GM aux cooler downstream of the radiator unit if you are going to be towing anything heavier than an EMPTY boat trailer.

Allan

ericnottelin

I would be very surprised if you didn't already have the aux cooler. Look, it is really easy to see it is there.

Additionally, I agree that this is totally normal. I pull a 8k camper in Florida (average ambient temp = 90 degrees). I usually average around 210-215 degrees. I was told anything over 240 was excessive. I'm not sure about any temps over that.

Another thing to keep track of, is the amount of time your tranny temp is over 200. Anything over 200, the tranny fluid breaks down faster. So, if you do this frequently, as I do, be prepared to change the fluid more often than the recommended 50k service interval.

I plan on changing the fluid over to full synthetic as it tends to run cooler.

country_09

Look right behind the grille. You'll see a small radiator lookin square there. If it's there, you have the stock gm tranny cooler. If not then you don't, but either way, if you pull often i'd upgrade it to the tru-cool 40k cooler. Much larger coolin capacity and will help out a whole lot

ericnottelin

I have to look into that. I hate that you have to CUT :O one of the tranny lines to add an additional cooler. Wish there was a way to avoid cutting the factory lines. Seems like such a waste...

country_09

Well worth it!

JohnDeere

Thanks for all the input!!! I'll do some thinking and looking.