hello, my name is Dave and I drive a 2003 chevy silverado 1500 ext cab w/ a 4.3 v-6 motor. this puppy weighs 6200 lbs.(ouch) I drive 60 mi high way and 15 mi city every day. I drive at 55 mph, & hate using my brakes, I replaced the air filter with an nk oil filter, I've taken out the back seat, pumped the tires to 45 psi, taken out the spare tire ( i carry a can of fix a flat ), I add marvel mystery oil to the gas, and I've taken off the tail gate. I get around 20 -22 mpg but that is just a guess because I never put more than 10 gal in at a time. HELP there is nothing more I can take off the truck to make it lighter. Any Ideas to increase my mph ?