Highest trans temp seen

[4wdriver]

Recently I noticed my trans temp at 235 degrees while working my truck in cold weather 20 degrees or so. Anyone notice temps that high. My old truck 2002 hd never went above the engine temperature which is why I’m wondering mostly. 

[txab]

Your still ok at the temp you experienced, thanks to synthetic fluids that can handle it. You don't want to make a habit of it. You might look into lowering it. By adding an external cooler to shed the heat faster thus keeping over all temp down

 

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[Black02Silverado]

That sounds kind of high to me.  I have been towing a 6,000lbs  trailer with my 2002 and with all the shifting it does, the temp maxed out at 185F.  I wouldn't think these newer 6sp transmission would run much hotter.  I know the fluid has come a long way now that it is synthetic but heat still kills transmissions.  Keep an eye on the fluid.  If it starts to turn dark brown then I would change it out.  I would change it out at 50k anyway.  I know what the manual states but fresh fluid never hurts and since you tow it can only help extend the life of you transmission.

[crankman]

That seems a bit high, I pull my trailer weekly year around and in the summer I've seen 180 deg and thats in town driving slow. If I get out on the highway it drops down to 140-160. 

[amxguy1970]

I've seen in upwards of 230ish but that was on Engineer pass in July while creeping in 4 low in traffic. I will change it a little earlier than my normal 75k most likely, still not worried and acts normal. Gotta remember the transmission cooler runs through the radiator and that sees 210 degrees steady and can get higher in slow speeds in heat and higher altitudes so the fluid running to the tranny will kind of reciprocate the engine and radiator temp at times...

 

Tyler

[MotionMan]

180 is as high as I have seen it, that does sound high though.  A big help is to not shut the engine off after towing, let it idle a bit, once the engine stops the trans pump does too.  

[SierraHD17]

Don't think I have ever broke more than 51 or 52 degrees C with mine.  So like 124F lol.  

[4wdriver]

When I mentioned working the truck what I meant was plowing a foot of wet partially frozen snow in a church lot which happens to be gravel and dirt lots. The job took about 1.5 hours but normally takes 45 minutes. I wasn’t unusually hard on the truck but it was worked hard if anyone has plowed in these conditions they know what I mean. Just like many of you other truck enthusiasts I love trucks and enjoy driving them but in all reality it’s main purpose is to be a tool of sorts to plow,haul,tow,etc. my old 2500hd never reached those temperatures and I know they are different animals in many ways but that truck was tough as could be and I want this truck to live up to those standards and not over heat at the hint of hard work. Even the old version had overheating problems and gm gave owners a new clutch fan to solve the problem which it did solve any over heating problems in the old truck. From the helpful comments here and other reading it looks like others have reached these temps but I will still ask the mechanics if these a normal temps under hard work conditions or if I have a cooling problem. 

[redwngr]

IIRC, the trans temp warning comes on at about 270.

 

 

[avalonandl]

These new fluids aree designed to work at 260.....Farenheit

[Skeld]

Plowing is how I get mine hot also, max I have seen is 210 I think.  I was a little concerned but so far no issues.  A lot of forward/reverse action jumps the temp up pretty quickly.