silverado13
GEAR HEAD
yeah the 3.42 would explain it, in my old truck i could get up to 20 mpg on the highway doing 55-60 if i was doing a trip, the truck i have now on the other hand has had vaccum leaks and O2 sensors and blah blah blah, ever since i got it and ive been slowly fixing all the problem but i know i havent gotten milage even worth tracking, like probably 10 mpg on the highway