I think this would be a huge performance gain but I'm kinda scared to do it. Also I'm AWD so it won't be cheap!Any suggestions?

 

I'd say go no numerically higher than 3.73's. 4.10's would be too much for the first gear. I would think it would make it nearly useless. The 6th gear would help the highway mileage though. On second thought go ahead and do it and let me know so I know which set to go with.

 

my 6.0 is seriously hard on fuel, wish it had 3.73's
better places to spend your $$$$
a tune would be a good place to start.

 

I wouldn't hesitate 1 bit to put 4.10s with the 6 speed...not one bit! It would equal tire roasting 1st gear, but it would be fun as hell imo!

 

4:10's got them in mine and love it. Anything else and you are wasting time and money.

 

4.10 with the 6L80 would = crazy 1st. Should be a wicked launch w/ AWD. Do it

I know someone has the numbers to calculate what the would be the equivalent of compared to 1st in a 4L60... probably like having 4.88s with the 4 speed

 

This is something I've beening thinking about doing with my '08 AWD Sierra Denali as well. A 3.73 gear might be better overall though, but that low first gear in the 6spd is what helps these trucks perform in the first place, so more is probably better, right?
I saw a thread on the HP Tuners forum with a guy who had done the 4.10s in an AWD along with a Yank convertor and was trying to solve some issues he had with the 6L80E shifting, so you have to bear in mind that there might be other problems/issues that might have to be addressed, other than recalibrating the speedo.
From what I recall though, the guy was saying that he also owned a heads/cam LS1 Trans Am and the Denali had better acceleration, and except for the tranny issues, the truck was a beast.
I would like to see what my 0-60mph times would be with this, because right now I'm running a 4.67 sec 0-60 (on a G-tech Pro) spinning all four tires through first gear with a 125 shot of nitrous and I'm about to install a window switch and/or a progressive controller to try to minimize/eliminate the spinning. 4.10 gears would probably mean I would have to run 4 drag radials!
It would be nice if someone who has done this could outline the parts needed (with part #s) and identify any issues and the fixes for them. I personallly think the AWD needs the lower (higher numerically) gear to keep up with the 2WD, from what I've seen.

 

Well it must do something for the trucks as GM just started shipping 6.2 Silverados and Sierras with the 6.2 and 3.73s. I'd be that would make things a lot better.