I have a 2004 Blazer LS 4x4 4d , the rear end is a GU6. I also have a donor 1998 Blazer LS 4x4 4d that has a GU6 G80 in it. Sooo by now the obvious question is can i just swap the whole axle setup to my 2004? the locker rear end will need new axle seals, and pinion seal though but those are not difficult to change out. is there any other issues I should run into if I swap this out? I believe the 98 rear end is a 7.5 is there a way to tell ? Since I know the parts store is going to ask me if it is a 7.5 or 7.6 or or..

from the 1998 ls donor blazer
1998 Donor... GU6 G80

 

Sounds to me like you have a simple swap and scored a g80. Are they both disc brakes? I know that theres a little more when it comes to that, but not sure about the rest.

 

yep disc brakes with drum parking shoes. Spent the morning finishing up my front end work though. New upper control arms, upper and lower ball joints, pitman arm, idler arm, inner and outer tie rods, new front wheel bearings, stabilizer links, and shocks. dropped it off for alignment . will be there a week because they are very busy with the snow that just fell and people are idiots. sooo I have some time to re-seal the rear end. prolly do backing plates, axle seals, pinion seal and rear end cover.