9inch splines?!

[rebel65]

Hey, i'm sorry to ask such a stupid question, but can you change what axel spline is in a 9" 3rd member?? i found one for 30 dollars and i am going to pounce on it if i can change it from 28 spline .... hope i can thanks and sorry again

 

[geostang351]

I think you are going to have to change the axles then from 28 to 31 to allow for this to happen

 

[dennis112]

Axle splines must match the ring gear carrier splines. You can't cross match them so an axle swap alone won't work.

You could swap out the whole center carrier to make them match, as the actual housing can work for both 28 spline and 31 spline applications.

 

[ForceFed70]

Like Dennis said, you'll have to change the center section as well as the axles.

But I also wanted to mention that the 28 spline 9" is still a very strong rearend. I wouldn't bother converting unless you plan on alot of power or hard launches with slicks.

 

[rebel65]

oh awesome..thanks again i'm sorry for not poviding much information as to what i actually meant. thanks a TON, i'll be trying to go pick this up then, i need a housing though.

 

[krash kendall]

It is actually the spline count on the bevelled spider gears inside the carrier that have to match the axle shafts.

In this picture you can see the gear with the splines behind the broken cross shaft. I pulled all the guts out and replaced them with a 28 spline mini-spool and made a new cross shaft. A 31 spline would surely have fit right in if I had the matching axles.

 

[rebel65]

heh cool pic... lol kinda, i also have the oportunity to grab a 79 f150 full rear drum to drum, and i was thinking i could mount up my discs to it..and prolly find some new axels at the pick n pull but the whole rear is for 50 dollars. so it seems like an okay deal to me. heh. and if it don't work i can always sell it again..not that i have a few of those parts around D: if i have to fsck around with the housing i'll be fine with that i got some time.

 

[dennis112]

It is actually the spline count on the bevelled spider gears inside the carrier that have to match the axle shafts.
View attachment 449443

With an open rear, this is true. All that would need to be replaced would be the spider gears.

With a limited slip type differential, such as a traction loc, equa loc, and the true trac, part of the carrier is also splined. In this case a full carrier swap would be required to use a different spline axle.