Searched this forum but couldn't find a good answer.
I towed with my 2007 for the first time the other day. I monitored transmission temps with my Livewire TS. Unloaded I usually see 150-160. When towing on level stretches the temps stayed 185-190 but on longer hills I saw up to 202. I was towing about 3k lbs but I had a lot of wind drag due to the top and windshield on my UTV so it pulls pretty hard. Ambient temps were mid 80s.
Coming from newer trucks that normally run 195-205 I was just wondering what is normal for the 4R75e?
I see my trans temps rise to 205 to 207 when pulling my 6200 pound camper up grades. I also monitor my engine temps, and they too will rise to over 200 during these climbs. As long as you see them drop on flat roads, you're fine I'd say.
Running a transmission oil cooler for towing is a must if you want to keep the tow vehicle in good shape transmission wise, along with frequent fluid changes.
I also run an engine oil cooler to assist in keeping its engine oil cool.