The frame is definitely different on 99-07classic. don't know for sure about GMT900's tho myself.

The conversion is usually quite expensive and more realistic to just sell the 2wd and buy a 4wd. But again. dunno if it holds true on the GMT900's

 

when I said front differential it will have to have the axles, and thast all needed, you dont have to put the whole suspension, I did the swap myself but you can do your research or hear other persons comments, I am just saying what I did.

Ed

 

Well since denali 08s the only one to actually do it then i believe him

How many people are interested in 6.2/2WD setups?

 

So someone needs to get some pictures of a 2wd to Awd or 4wd.. at least the front diff mounts and such.. I can picture how i think it mounts, but without laying under a truck and seeing for sure its hard to picture for sure..
I hate to think its that simple.

Other thing is that i wondered about the wiring and things accompanying the AWD setup.. Mine is 2wd so what would be needed?

Come on with the help.. Check out the 2wd to 4wd/Awd thread.. post up info.
Model numbers on the case and such..