Different gear ratio front to back

[dcw57]

I searched and cannot find anything on this. Probably because I'm the only one inexperienced enough to ask. My 09 4x4 Silverado needs the rear end rebuilt. I know better than to diy it so I want to have it professionally done. My question is, it has 3.73 ratio and I have a 3.08 with the same exact features as my 3.73. Active brake, posi, stabiltrac, all the rpo codes match except the ratio. I'm pretty sure I can't put it in there permanently and run 2 different ratios. My question is, since it takes weeks or months to get the rebuild done, can I put the 3.08 in there so I still have something to drive, as long as I don't engage the 4x4? Thanks in advance.

[WilliamBos]

You cannot run 2 different ratios, they must match.  Why would it take so long to rebuild?

[dcw57]

thats just the way it is around here. the shortest time ive been quoted is 6 weeks. I pretty much knew they had to match for the 4 wheel drive but if i run it only in 2 wheel drive it still won't be ok? thank for the reply

[davester]

If it's straight up 2wd, and not some kind of auto setup, then it will be perfectly fine just doing one of the diffs at a time.

 

It's only a problem when both the front and rear diffs get power to them at the same time.

[CamGTP]

He could even take the front driveshaft off if he needed to.

[dcw57]

Thanks guys, I just wanted to make sure I wasn't going mess up something. I don't know much about preload and backlash or have the tools. The .308 is for sale when I get done with it if I don't break it too. I appreciate the help.