I'm pretty sure it was in 2nd. It was also in 4wd. It sounded like the cooling fan was tacked out! Next time on approach I'll manually keep it in second. The coolant was running in low 200s along with the oil. It's the worst conditions for the tranny, slow steep grade and loaded down heavy.
My temps typically range 168-173, and seem to be dependent on outside temps. This hill is especially hard on rigs, I had it in 4wd the whole time towing around 19k GN with equipment. I'm going to be hauling steers tomorrow around ranches and will see what it does.
At that slow speed up a steep grade, 220F max is not unexpected for a load that big.
You can't prevent a downshift, but if it's shuttling between 2nd and 3rd, it might be best to limit it to 2nd and prevent those shifts that are creating more heat. If you have to go slower, or run in 1st I'd consider using 4-lo or also consider getting a 2-Lo lockout box. The only downside is 4-Lo (or 2-Lo fake) turns off the EB.
With the loads you're running, you may want to look into an aftermarket thermal bypass valve to replace the stocker if you're in a consistently warm climate.
Not sure if this Mishimoto fits 19+ but it has the option to run a bypass or thermostat.
The transmission is the backbone of your 2013–2018 Dodge Ram 6.7L Cummins. It’s responsible for transmitting up to 930 lb-ft of torque from the engine to the wheels. That much power generates a lot of heat and if that heat isn’t dissipated, it can destroy
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