2007.5 68RFE OVERHEAT QUESTION

[MJarske]

So, I have had this truck since new. 2007.5 2500 MC. Been cross country 4 or 5 times never had an issue.
I was pulling 12,000 lbs trailer on a 19 mile grade super curvy forest road so speed was slow from 5 to 15 mph. 2nd to 3rd gear.
My Trans temp idiot light came on for the first time ever. I stopped set idle at 1500 and light went off after 15 minutes or so. This repeated about every 2-3 miles until I topped out.
I assume the torque converter was not staying locked up creating heat?
5 days later pulling out I had the same problem, put truck in 4 low to assist with down grade to save brakes and keep rpms up for engine brake and Trans no longer overheated on uphill grade. Now I want to do 2 things, deeper transmission pan and add Trans temp gage as these trucks did not come with one in 07. Changed ATF, it was still pinkish but not red, after ATF flush at oil change shop fluid still looks pinkish not red.
Before I add new pan and change filters is there something else I should look for?
Oh, and a guy stopped to ask if I needed help, he had a 2016 ram 2500 towing 6k, said his Trans overheated on same grade twice.

 

[AHutson]

At that slow of speed the torque converter won't lock up. It won't lock up until a little over 30 mph usually. I read in the owner's manual that any slow towing is recommended to lock it into first gear only to prevent overheating. I have an Edge Insight CTS 2 on my pickup, noticed a big difference in my trans temps doing this when I have to go slow. I also noticed a significant drop when towing after putting on a May-Hytec pan. If you don't want to put in a separate temp sensor and gauge an Insight will read and show you the temperature the truck's computers see. Only other thing I would look for is any abnormal behavior, overheating can cause unseen issues that may show up as odd shifting and shuddering.

 

[Ozymandias]

As he says, you need to pull that handle down. Drivers input is very important.
Some places like you found out even low range is appropriate.

 

[AH64ID]

I tow similar grades each year. There is a big reduction in trans temp with the trans limited to 1st gear.