Outer CV Joint - Manual vs Auto (Page 1/1)
Wichita JUN 19, 01:01 PM
Currently doing a motor swap and working on the axles.

My question is the dimension differences between auto and manual. I currently have the OEM manual axles and using the outer CV joints but not the axle bar itself.

I was hoping to use the spider from the swap axle to fit into the Fiero's race. It fits, but a bit loose. The ball bearings for both Fiero and donor are exact match.

I did try to fit the donor spider and race into the Fiero CV cup, but it's too loose. It doesn't exactly slide in and out, but it isn't a snug fit. I determined the best combo would be Fiero race and donor spider.

But I don't know if this will cause some issues, because the donor spider is about 2mm smaller. Maybe that's within tolerance spec, maybe not.



After combing through PFF on axle swap threads, I noticed the Auto CV joints were smaller. So I thought that maybe switching from manual outer to auto outer would help with me using the donor spider and cage. But I don't know. Just wondering if someone had a Fiero spider and cage from an auto axle that they could measure or donate/sell for me.

This is a picture from the thread showing the size difference.



https://www.fiero.nl/forum/.../HTML/000116-25.html

[This message has been edited by Wichita (edited 06-19-2022).]

Wichita JUN 20, 10:07 AM
I went ahead and bought a pair of reconditioned (actually two passenger side) ones from Rock Auto. They had some closeout ones for a good price, so I will be able to answer my own question once I get them and disassemble them.

fieroguru JUN 20, 12:54 PM
I knew I had some detailed drawings of the outboard CVs, but they don't detail any of the dimensions of the star balls...

Fiero Auto:


Fiero Manual:
Wichita JUN 20, 06:43 PM

quote
Originally posted by fieroguru:

I knew I had some detailed drawings of the outboard CVs, but they don't detail any of the dimensions of the star balls...

Fiero Auto:


Fiero Manual:




This is very helpful. Thank you.

The CV cup outer dimension difference is about 7mm. So maybe it might be a wee bit small, but I'll let everyone know when I disassemble them.

I also notice with this info that the auto is .295 shorter than the manual. This is also helpful, as the axles were a tad bit long and I was measuring to get them shorten and resplined. I may not have to now. Crossing my fingers that this will work.


Many thanks,
Wichita JUN 26, 09:00 PM
My first attempt with remanufactured axles were a bust. I purchased two. One was very similar to my manual ones.

I disassembled that one, although it wasn't the original OEM snap ring version, the guts (race and star) were the same dimensions, same for the outer CV cup. No difference with my OEM manual axles.

The other remanufactured one was beat up all to hell. You can tell it was a low quality Chinese knockoff. It has a weird brass compression ring instead of cinch metal bands on the CV boot. It's unusable as the splines were damaged, so I didn't disassemble that one. I was able to process a replacement for that one because it was damaged.

So I'm still on the hunt for those smaller automatic axles.
MulletproofMonk JUN 29, 08:45 AM

quote
Originally posted by Wichita:
So I'm still on the hunt for those smaller automatic axles.



So you just need the outer from an automatic axle? I'm pulling a 2.8L from a car that is going to scrap. I am going to use the drivers side auto, but could cut the passenger outer cup off for you... Drop me a PM if you are interested.

------------------
-Brian

My 87 GT Poly Suspension Upgrade (all pics) thread
Removing the roof panel
My HUD install thread
Modified stock air canister and base to 3.5 inch for 3800na

Wichita JUN 30, 12:54 PM

quote
Originally posted by MulletproofMonk:


So you just need the outer from an automatic axle? I'm pulling a 2.8L from a car that is going to scrap. I am going to use the drivers side auto, but could cut the passenger outer cup off for you... Drop me a PM if you are interested.




PM Sent