Did you readjust all trans shift points & speed cal's...?

 

yep...

 

deffinitely agree

 

It blows me away when I see this; 4.10s improving mileage. I guess it's due to pedal effort needed. But on HWY, that seems only downside for MPG.

 

well at 70mph its a 200rpm difference from 3:42s to 4:10s im pretty sure....so nothing drastic....

 

Actually it's about 400rpm

 

It's only like 450 rpm on a 30" tire from 3.42 to 4.11, so close enough.

http://www.race-cars.net/calculators...alculator.html

 

I went from 3.42 to 4.11 and so far is the best mod I've done (cam/LT's/tune/etc), the truck pulls a lot harder off the line and my mileage in town went up.

On the highway @ 70mph I get like 16mpg so I lost around 4mpg with the gears but it's worth it IMO. Besides if I slow down to 65mph I get 19mpg so no big deal, I almost never drive in the highway anyway.

 

3:73s + cruise + downshifting all the time = sucking the gas...

4:10s + cruise + no downshifting = better gas milage..


This was with heavy 20" rims and tires. Running a factory 16 and a short tire and yeah there are probably some differences.

 

I hate that my 4.8 3.42 can't hold cruise going up a slight incline without downshifting into 3rd... But I love the low rpms on the highway, just need more powa.