I have an 07 3/4 ton suburban with a 6.0L engine. My question is that I pulled my small rv (5000 LBS loaded ) over a fairly long ( 4 miles) and steep grade and noticed my transmission temp was reading at 223 degrees. I was in 3rd gear with tow haul mode engaged and doing about 40 mph. Is this temp normal or should I be concerned?

Thanks
Jeff

 

try this link

https://chevroletforum.com/forum/sho...ght=trans+temp


Oh and welcome to the forum

 

Amazing. Those newer cars actually have transmission temperature readers as well?

I dont know about transmission temperature readers. I do know this : when the temperature in your engine gets too high, then the Fans will start working, causing it to suck in cold air to cool down the radiators. So if at a certain point your fans kicked in, there is nothing wrong with your car. Of course, it does seem as if you pretty much got to the limit of your cars' possibilities.
This rises 2 questions to me :
1) was it really necessary to stick in 3rd gear? Because if you keep your car running on high rpm, it will indeed heat up a lot.
2) did the temperature drop , once you were on the top of the hill? If so, then there is nothing wrong with the car.

If you want to be sure though , start your car and let it run idle for a few minutes. It should rise the temperature needle(s) to the middle and a little bit beyond that point. Then the fans should kick in and get the needles back to a certain degree. If your car does that when standing still, there really will be no problem.


If you tend to do that much hard work with your car, it might be wise to put in an extra radiator to cool the transmission seperately.