My truck gas mileage and tires.?
I own a 99 chevy silverado K1500 4*4 and when I purchased the truck it had wimpy LT245/75R16 tires on it. I recently beefed it up with LT285/75R16 tires which are much nicer. My insupportable is that I used to get 13 mpg and now I get about 11.5 and the speedometer is still right on. I was wondering if this will cause any extended term damage to my truck. Everything seems to be fine and I was told that this is as big as I can go before switching gears out. Is this true or am I damaging my truck?
you wont spoil the truck, you have thrown off the miles on the speedo but not by much. your loss of mileage may not be as bad as you think because your odometer thinks your customary less miles than you actully are. 5-8% or so. if you haven't lost power you could go bigger, i stand up for you tune the computer with a power tuner to recalibrate the speedo and fix shift points of the tranny