Truck isnt happy pulling trailer
What gear ratio? tire size? Mine has 3.55 and 285-65-18 and it can be a dog at times.
When towing it is ideal to be in 3rd (overdrive off) and have that torque converter locked up. When the TC is locked your transmission temps will stay much cooler. On a hill I will drop into 2nd and make sure my TC locks up vs. staying in 3rd unlocked. Its not worth damaging your tranny trying to tow in OD.
There is a setting on your Gryphon that will tell you what gear you are in and when the TC locks up. It almost sounds like you are shifting into another gear when the TC locks.
I hope this helps.
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