Since Ive owned my suzuki sidekick I get if I am really careful 30 mpg, but on average 23 mpg. I assumed it was part my driving style, 3 size larger tires and 20 psi inflation.
I changed all the gear boxes to synthetic mobile 1 oil, engine to a 5w20 volvine synthetic blend and replaced all the brake parts. Had a frozen cylinder up front. I also went from the auto locking hubs to manual lockers, new speakers and wires. I dont think that did anything, but it was also done.
Takes less throttle to go and coasts further. 0-60 seems about the same and I do not FAS. Biggest improvement is I can enter 5th gear at 30 mph and accelerate. Before I had to go almost 45 before entering 5th and if I slowed to 40 had to drop back to 4th to accelerate.