Questions on towing with a lifted truck
First off, this is such a great site. I did a ton of reading and research and it totally Influenced me to go out and buy a brand new GMC 3500HD and a 35ft travel trailer. I've never owned or even towe...
Forum Discussion
From stock GM tires (about 31") to 35" you are looking at about a 11% overdrive from stock gearing. If you are close to your towing limits, this may make a difference. My Ford came with tires ranging 31-33" tall. When I bought it, I had the shorter tires and went to the taller ones after they wore. Although My tow rating did not change, I could tell the difference in the shift points when I towed my 11K+ lb trailer through the mountains. Where I was holding a particular gear, the 6% overdrive now had the transmission downshift one gear lower. I did see a slight rise in unloaded highway mileage with the taller tires, but towing was the same. In my case, the change to a slightly taller tire was not detrimental to mileage but it did make the engine and transmission work more.
