I lifted my 2021 silverado RST on 35x12.50x20s with a 6 inch lift and my MPGs went to s**t... I expected a little bit of a decrease but I've seen it go down to average 9-10, when before I was getting 14-15 regularly. Now, I can only average 15 with cruise control down the highway for half an hour.
I've looked around seeing people saying to calibrate the computer for the new tires? Would a dealership do that or an outside company?
Also regearing was an option too for better MPGs? I just dont want to spend 80 bucks on gas every 5 days haha.