I am in a 2006 4x4 regular length. I get 11.5-12 in the city (85%) around 16-17 on the highway. I am not lightfooted, but I tried for 45 days and did not see any real improvements (did not unhook the battery for trans reset though, just a little justification test for myself). It gets about the same as my 2003 2wd supercrew got. Thanks, Mike.