long time lurker first post
my truck wont slide nicely in the rain
keeps draggin that damn inside tire


i have a 94 4x4 blazer w/ open rear
and laying in my shop i have a 83 trans am 305v8 disc brake posi

from my google-fu they both have a 7.5 ring gear
can i just swap the differentials and use my blazer ring gear

also can i swap the disc brakes over

i have drums now in my rear with an open diff

do i use the shims from my blazer diff or the ta diff?

do both these axles have c-clips/eliminators? if diff which ones do i use?
what about spline count/axles
do i use the ta or blazer axles



are there parts i need to source before attempting the swap

thanks
reagor

 

You will have to setup that diff into the other housing just like it was a new diff. That means measuring shims, etc. You should first check to make sure that the carrier series is the same. If your axle has 3.73's and the other axle has 3.08's or anything below a 3.42, the carrier may have a different ring gear offset.

As far as the spline count and axle use goes, it's probably best to just take a peak at them both. Both should be c-clip axles, but the width of the axle may be different. A quick measurement from axle flange to axle flange (without brake drums/rotors on) will tell you if they are the same or not.

For the brakes, you will want to measure from the axle housing flange (where the brake backing plates bolt on) to the axle flange itself and compare between the two axles. If they are the same, then the parts will swap over without issue.

 

Ok thanks
Is there any worries about strenth? Like the posi is for a car and this is a truck
Weight rateings and what not?

 

It all depends on what diff is in that axle. One thing is for sure, if using LO range, you can put more torque through that diff than was previously capable. But that depends on how you use your truck.

 

so i just took apart my doner axle

it has 26 spline axle and the firebird posi with a 7 5/8 ring gear

as per this post i have 28 spline axles
http://forums.myspace.com/t/4525010....ums.viewthread

replacement axles for my truck are 29 inches long 28spline

i dont wanna pull my truck rear if it is not gonna work right

any way i can use the firebird axles too?
30 5/16 is the replacement length

the firebird has discs and the blazer has drums...if i use the discs too will that makup the differance in lengthes
it 29inches from the bearing mark to the end of axle

the lug pattern matches up ie rotors match my drum lug patern


any way to run my vin and tell me the internal specs of my open rear
94 blazer 4x4 4.3cpi

 

anyone want to buy a disc brake firebird posi
26 spline axles
$350 (what i paid) pickup or buyer pays shipping
pm me
located in nj

 

even better if someone has a post 89 posi(28spline) they would like to trade for a 83 7.625 26 spline unit would be awsome