Tow Haul button does nothing

[SnoKing]

I’ll bet you were already cooled down and just maintaining temps when at idle. Start with a cab at 110* and see how well it cools off at idle only

Yep, the truck did not sit at the store over night, as I drove there.

 

[Dick Langendorff]

We just returned from the Cummins event, 7,600 miles towing a 5700 lb Lance and we averaged 11.61 for the entire trip. That was at 70-72 with the cruise on almost the entire way. Have a little over 15,000 miles on the truck when we got back.

That is impressive. At least you stayed under 75.