2002 4x4 V6, everything was fine, and then I did 2 things to my truck. Milage since has been very poor, with about a 3 to 4 mpg drop. First thing I did was put a ARB bull bumper on my truck. Other thing I did was use CRC throttle body cleaner to clean the throttle body. I did both of these things within a tanks worth of gas, so I just don't know which one messed my mpg up. I kinda figured that the ARB bumper was to blame, but then was wondering if the throttle body cleaner might have fouled up my O2 sensor or cat somehow. Or if possibly there was some other reason why cleaning the throttle body the way I did (std. procedure) could have messed something else up. It is definately one of these two things that has made the mpg go down. Anybody have any experience with ARB bumpers and if your mpg went down? How about cleaning that throttle body? Is it possible that the cleaner messed up the O2 sensor or cat? The truck drives great, but the gas gauge practically moves while I am watching it.