1500 yukon xl tow mode

Many people towing with naturally aspirated gas engines like ours do get slightly better fuel economy towing in one gear higher than sometimes needed. This is because you are using less available torque. For example 25% accel pedal in 3rd at 2500rpm vs. 50% in 4th at 1800rpm. Also, little reserve power means speed drops quicker on hills. Then it finally downshifts two gears and tries to make up for the speed loss.

My prior TV was a 2003 F-150 5.4L 3.73. It towed very well in 3rd gear. It was a little happier at 3000rpm than 2500rpm, but that would be about 72mph. 4.10 would have been perfect.