1996 vortec 5.7l gas mileage

[largewon62]

I have a 1997 Yukon with 180 miles. With 285's and 3.73 gears I get around 12.5-14 combined mileage. Thinking about swapping to 4.10's to help my around town mileage. I calculated that my rpms should be the same as with the factory tires and 3.73s.

 

[Bondovw]

How? That's great mpg the best I got was 15

Is yours a 5 speed?

 

[AllThrottleNoBottle]

With my 2000 Escalade (Tahoe in a tuxedo), 3.73's, new GM crate L31 and everything new (sensors, injectors, cats, distributor, hell-even the starter), I get about 12.8mpg combined (mostly city), best was 15.5 all highway, all city fully loaded around 11.5. Heavy *******, who cares, it rides, well, like a Cadillac (truck, that is!)

Actually, I thought something was a little off (low) on the mileage until I started hanging out here on GMT400...and learned to say phuck it!

 

[gstubbz]

My 98 ECSB Z71 averaged 12. Consider in 199k when it left me and gnarly rod knock since I bought it at 165k. I wasn't easy on the poor thing either. 3.42 gears and 265/75/16 tires