4.56 or 4.88's. There's hardly a difference between the two. With 4.88's you will be spinning about 2500 rpm at 70 mph.

That's the same as my 4.8 truck with 31" tires and 4.56's. 4.56's are the best thing I ever did to that truck.

 

Is this with the stock stall? Id be happy runnin 2k @ 70

 

The converter is locked on the highway, so it doesn't matter if it's an aftermarket or stock converter.

 

So how would it effect city driving?

 

If you want 2k at 70 you'll want 4.30 over the 4.56 or 4.88. I've got 33s with 3.73s and would prefer 4.30s, but they're not available for my differentials.

 

What differential do you have? Also, I have the rearend with drum brakes, are they worth putting money into or should I consider something different?

 

All of the 6.2s (except AWD Denalis) have 14 bolts. You have the 8.5" 10 Bolt. When beefed up the 8.5" can hold decent power, so I wouldn't be worried about upgrading if I were you.

 

I have a 2011 4x4 with the 14-bolt rear; I can't remember if it was the front diff or the rear (or both) that the 4.30 is not available for. Your 10-bolt will be just fine unless you have really big plans.

 

Im leanin toward the 4.30s, what do they normally cost and where is a good place to get a set?

 

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