Changing Gears

hollis092 · August 20, 2013

So I am considering changing the gears in my 2012 from the current 3.08 to 3.73.

Has anyone done this? Wondering on performance increase, fuel consumption.

I do alot of running around in town and the 3.08 just doesn't cut it for me. Not only is it a little sluggish on take off, I'm sure it greatly impacts my fuel consumption in town since I never really get up to speed.

My old truck had 3.73 and would burn the tread off the Grabber AT2's I put on it.

I'm not even sure what thought process GM was on when they put these gears in the newer trucks.

Found the OEM G2 3.73 gears for around $300 and could probably handle the install or have a local shop do the work. Question is does GM support that? I know I would need to have the ECM updated to the new gear ratio after the install but want my warranty intact as well.

RWD - so don't have to do differential.

hollis092 · August 20, 2013

Mods feel free to move this if needed.

takethebounce · August 25, 2013

I was looking for a truck recently with 4.10 and could only find ones with 3.73. I called a GM dealer that I have dealt with lots and they said GM would not give them the proper unlock codes to do the ecm change. They said just get a handheld programmer that will allow for the gear or tire size changes.

The local gear shops wanted $1200 per axle installed for the gear sets then the $300 for a programmer, I just waited to find a truck with what I wanted. If you get a programmer make sure it has those gears in its calibration.

Do an internet search, lots of guys have done this.

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Daryl LBZ · August 26, 2013

The only semi helpful thing I can add is that I get 14.3 mpg with my 3.73's, but I have the 6.2. I would imagine that with the 5.3 you would get better than that.