I think my truck has 3.08s in it now and I would like to upgrade rear ends. I have an 05 CC 1500 2wd with a 5.3 what seems to be the best ratio for these trucks.

 

cant go wrong either way...i would do the 4.10's in a crewcab

 

Anybody with 308 or 323's will love life alot more with either. How much highway driving will it see? Get some and

 

It doesnt really see awhole lot of highway riding. Most of it is in town, and I was thinking the added gearing would help the gas mileage if I stayed out of it in town or would have little effect. Just because with better gearing it would be able to get the truck moving easier.

 

I would decide what size of tires I want, then I would calculate to end up with either a 3.73 or 4.10 ratio. If you are wanting more performance, go with the 4.10, if you are more concerned with economy, go with the 3.73. In reality though, I don't think you would notice much difference between the two. Either one would be a world of difference from 3.08.

 

The tires on my truck are a 275/30/24. So they are maybe an inch taller than the stockers.

 

How will I know for sure what kind of gears I have? What part of the VIN do I need to look at and what are the break down of the codes?

 

Or you can go in between the two, 3.90's.

 

4.10!!!!!!!!!! All the way!!!

 

You have 3.23's they never put 3.08's in a 99-07 truck