Hey guys, I read the FAQ:10 bolt sticky and it said the axles are interchangeable from drum to brakes and vise versa. Is this only if the splines match? My 84 has disc but an open diff, but my 92 has posi. Would it be possible to take axles and posi out and put them in the 84 if the ones 28 and the other is 26 spline?

 

Yes, you can swap the 28 spline differential and axles into the older housing. You must reset the pinion depth, bearing preload and backlash if you are changing the gears.

 

Bad ***! Yep, been studying up on backlash. I'll look into the others. Thanks Big Gear Head!

 

I'm just wondering, why not swap the whole rear end?

 

Because I wanted the disc brakes. Now though I remembered when trying figure out where to add more oil to the diff on my 84 the vent cap was suppose to be on the driver side. It was on the passenger side, and for the 10 bolt only had 1 year 26 spline like that. So Im 75% sure my 84 has 28 spline. So im just gunna put the posi in from the 92 in the 84.... Hopefully lol

 

Ironically a 26 spline just came out of the '92. So I now I might have to swap them.

 

All 7.5 rear ends had 26 spline axles up to '90. The 28 spline upgrade was in '90 and all 7.5 rear ends after that had 28 spline axles. If you took a 26 spline axle out of a rear end then it's either an earlier rear end than a '90 or someone swapped everything inside with earlier parts.


The vent in all of these rear ends is on the right side (pass). You don't add oil through the vent.

 

Yup; a few cars, mostly in off-the-wall gear ratios, got the 28-spline in 89, but very few. All got them starting in 90. (not just these cars; S trucks etc. as well)

If you have 26-spline in a 92 car there's been some swappage in its history.

They didn't change the center housing casting at all during the production run of these cars AFAIK. Vent was always in the same spot.