greatskiiiier

http://www.ls1tech.com/forums/gears-...-rear-end.html
posting these everywhere i can get it

The Story- im getting a free 3rd gen rear end with an eaton posi and 3.73s, the rear is 1.5 inches shorter so id have to get spacers..

My Questions-
- can i put my 28 spline axles into the eaton if its a 26 spline (assuming its a pre-90 rear)(just searched and seems like 26 and 28 splines are equally strong)
- can i swap the interals into my housing so that i dont need to get spacers
- is it shorter 1.5 inches each side or overall?

I have a 1998 Z28 with a stock 10 bolt with 3.42s... I'm going to put this rear in even if it only lasts the summer, but if i can make this more perminate, that'd be nice

87DJP2001

If the 3rd gen rear is for a 26 spline axle you are SOL. Some reasons: 26 & 28 spline counts do not interchange with the same internals. If you try to use the 3rd gen axle shafts with the 4th gen axle housing they will be too short.

The only parts you can use are the ring & pinion.

greatskiiiier

ya i know that... if i stick with the 26 spline, ill jsut be using the 3rd gen housing, with say 1inch spacer on each side (itll look a lil narrow but w/e) but if i were to do the 28 spline, id want to put the internals into my 4th gen housing and use my stock axles... im jsut not sure if they'd fit if the internals were setup for a 26 spline...

87DJP2001

NO...28 spline axle shafts will not work with the 26 spline internal carrier.

greatskiiiier

does anyone know the diameter of the 26 spline and 28 spline axles? is there much of a difference? how much power will it take to twist one of these bad boys?

87DJP2001

What are you trying to do??? The body diameter of both shafts should be the same and the spline end should also be identical except for the spline count.

greatskiiiier

perfect, i found that the 28 spline torque rating is 3800 lb ft im only putting down 2800 right now and 3080 with the 3.73s, jsut wanted to make sure they werent like .25 inches smaller and they cant even handle 3000lb ft haha... so this axle should be awesome for under 200 bucks ill have an eaton and 3.73s NICE

Stephen 87 IROC

82-89 third gen 10 bolt diffs have 26 spline.
90-92 third gens have 28 spline.

If the diff you're getting is 82-89, you can easily buy aftermarket 28 spline axles for it.

If the diff you're getting is 90-92, you can pull the carrier and gears out and put them into yours.

greatskiiiier

if 87DJP2001 is corrent about the diameters, then the 26 spline should be jsut as strong, (take that the inside diameter be slightly smaller and less surface area) the overall torque rating should be very simular and way about my powerband... so on to the next problem

- can i fit my stock rims in the wheel well with the axles being 1.5inches narrower? or will 1inch spacers work? (save the extra money from getting 1.5" spacers)

camarobird92

What is wrong with the factory posi in your Z28?

sn8ke eatr

this guys making too much powa for 10 bolts... hes just putting off the inevidiable

quickchicken

if he wants to avoid the cost of a 12 or ford 9 he needs to find a borg 9 bolt. IMO thats what the 4th gen gang should have gotten from the start. 3.73 ratios are easy to get for the 9 bolts.

greatskiiiier

haha, as stated im getting this for free, so why not take off a tenth with 3.73s in the process... if it came time to pay for something id go 12bolt. i figure with this i can get a girdle and spacers and when i go that route, i can sell them fairly quickly

sn8ke eatr

cause ill have to help you install it

ws6transam

You can swap third-gen carriers with fouth-gen carriers and vice versa so long as you keep the spline count the same. Axle lenths are an issue though, as you can't put your fourth-gen axles into that third-gen axle assembly without exposing too much axle to the elements: The bearings will be riding on the wrong part of the axle, as well the seals. You'll also risk bending or even breaking an axle if you try that.

However if you get the correct length axle, you can swap 10-bolt carriers back & forth between third-gen and fourth-gen applications, no prob.

I once had a set of Richmond 7.625 gears that I used to replace my stock 7.5 inch ring & pinion on my Eaton guv-lock 26-spline carrier. I later upgraded and put those same gears onto a Gleason/Torsen differential from a 1999 SLP Firehawk, then swapped the whole thing into my 1984 axle assembly with some new Moser 28-spline axles and it worked like a charm. This proved to me that housings are interchangeable from 1982 through 2002, so long as you keep the spline count and the axle length straight.