sleeperlqx

iTrader: (3)

Exactly why you are going in the wrong direction! Your truck is going to be shifting gears back and forth UN-necessarily, and make much more work for it to do to get the same acceleration. You would be better off switching your 4.10 to a 4.30 or 4.56! It will make the engine do less work, and keep it in the powerband, and not allow it to switch gears for no reason.

Add a load, and tow it will be magnified!
4-500 rpms down is not going to increase gas mileage
4-500 rpms UP is mostly likely going to increase mileage

Keeping the engine in the torque curve is what will increase gas mileage. I dont care how many hwy miles you are doing.

mhotrodscooter

iTrader: (13)

I get what your trying to say, but I went from 3:73's to 4:30's in my ecsb. Went from 18-19mpg down to 15-16mpg. Since that swap I changed cam & a couple other parts & my tuner & now I'm seeing 18-20mpg.

PitchblackC3

iTrader: (3)

You can't really compare the fuel savings at different speeds and think that equates to the fuel savings at different RPMs.
The air resistance increases exponentially with speed.

rumblebox

iTrader: (9)

Im considering this as well. With 4.10s and the cruise set between 80 and 85mph i consistently get 13mpg at 2800rpms. I average 12mpg in town. I get almost 17mpg around 65-70mph. Im thinking the RPM difference will render me better mileage since i dont pull much with it anymore.

It has long tubes and a half *** tune. I need to get a wide band.

nonnieselman

iTrader: (10)

The size And weight of the tires could be one issue.
Could you find some stock 245s to try? They are lighter and shorter. 30.5" tall.
Compared to the 32s it would raise your rpms at 70 just a lil. Be worth a shot and see what happens. It dont look near as good but your after mpg and not looks right?

mhotrodscooter

iTrader: (13)

I'll try this when I get home. This would be more of easier & cheaper test. I just know its going dumb with smaller tires. Gas prices at the pump or dropping so I might just leave it be for now