Mpg

[Alliance00]

Got a question for you all!!

 

 

The M30 Transmission in the Avalanche has a high gear ratio of .70 and the gear ratio in the new 6spd is .67 and the rear end gear is going from a 3.73 to a 3.42 any idea what the MPG increase will be??

[Rocco715]

Miniscule. You will loose more towing capability and acceleration with the 3.42 (if that matters to you) instead of 3.73 than you will gain in mpg

[Zembonez]

Almost nothing.

[Big Whiskey]

Not sure what the bottom two gear ratios will be, but they better be pretty low. If not they will be a turd off the line and mileage will suck. I know, I put 285 tires on an 06 Z71, 3:42 gear, truck. It has no power, sucks gas like crazy, and won't stay in overdrive. Other than that........I love it!

[05silvycrew]

cruising at highway speeds, i'd guess 1 mpg better. assuming the same size tires, you're going to drop 100-200 RPMs which should result in better fuel economy on a trip.