December 24, 2010Ive seen almost 17mpg highway on my 98 5.7 stock size tires and 3.73 and a topper. Full syn in everything
Forums : Performance General : MPG record (2831 Views)
September 30, 2011OMG? Im not a four wheel drive guy but I guess that`s good for what you guys drive. I drive a 2009 Sierra 1500 5.3 liter with 3.42 gears. I average 15-18 in town and without my bullydog tune I have average 20-22 mpg highway at 65 mph and with the performance tune installed I have seen 23-24 mpg highway at the same speed. I might add that I also have the bullydog intake, sprint booster,jet performance mass airflow sensor, and royal purple motor, and gear oils. If you guys don`t have programmers it may be a good investment?