What is Normal Transmission Temp While Towing?

[CEtaco]

I am about to tow my RV (4100 lbs) from Virginia to Utah. I have read several threads and comments that have said the transmission will sometimes overheat when towing for an extended period of time up a grade. Several have said sometimes you have to pull over and let the transmission cool for about 30 minutes. I can monitor my transmission temperature via my Cobb interface. What is normal transmission temperature while towing in the 4g taco and what temp should I pull over and let it cool at?

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[GSPHerder]

My 2026 tranny will overheat in 2Hi when I'm in driving around dirt roads. When I shift to S-Mode and keep it in a lower gear the tranny temps drop fast, so if and when your temps start climbing try S-Mode and a lower gear.

Id start with something like this:
175°F (79°C)Normal operating temp
200°F (93°C)Fluid life starts shortening noticeably
220°F (104°C)Oxidation increases rapidly
240°F (116°C)Varnish/sludge formation begins
260°F (127°C)Seals harden; clutch damage risk
300°F+ (149°C+)Fluid can fail very quickly

I think once your tranny hits some of those temps it probably makes good sense to change it.