Stub axles, custom or is this common?

[Mike Simard]

I have a Timken hub assembly I'd like to use but need a stub axle.
It's a 27 spline that measures about 1.18" and has 2.87 'length', it's used in 2002 Ford Explorers and has the 5 x 114.3 pattern I want.

This unit would be handy to use or I can keep looking for a hub assy if needed. My car is custom and I already made uprights for certain hub bolt patterns. Now I want to upgrade for a bigger engine going in. I could always make new uprights if this was an oddball and I'm missing out on a good, common hub to use.

Does anyone recognize this spline and recommend a stub axle supplier?

 

[Phil]

Mike:
I am using a Ford hub from the Mustang Cobra, 28 spline, but I don't know the diameter or length dimension...some internet searching would probably do it.
Ford also sells the hubs in their motorsports catalog with a 5 on 4.5" bc along with the bearings and other stuff...but we always get the bearing on the outside....much cheaper.
The half shafts are very strong...especially the cobra ones but godawful heavy..someone like the driveshaft shop could make them up for you and fit to your inner cv joint and you would be good to go.
Good Luck
Phil

 

[Mike Simard]

Thank you Phil, that made me remember I have some Superformance Cobra axles here and I just learned something interesting.

The outer CVs are 28 spline like you mentioned AND they are the same as Porsches. At least 928s (which use 108mm CVs and never break). The Ford is about .3" shorter.
The axle splines (inside the CV) are different.

As far as I know, there are no handy hub/bearing units available for that Cobra or Porsche 28 spline. Isn't the Cobra bearing assy built into the aluminum upright?

As for custom axles and parts, I'm not going to use the Driveshaft Shop anymore. I found them to be lazy, sloppy and unreliable.

 

[Phil]

Mike:
Good info on the driveshaft shop...I never did anything with them but all the mustang guys seem to use them for some reason.
On the subject of the bearing, it presses into the upright and there is a nasty snap ring behind it, it is commonly available at any bearing supply or auto parts store..I don't have the number here at home but when I get to the shop I can surely post it.
The hub has a mild press fit into the bearing, and the outer CV/Stub pushes thru from the inside and has a big nut (36mm) that one just tightens to spec...like 100 ft/lb or so.
The bearing is actually two inner races inside a common outer shell so there is no pre load or shimming per se...just make sure it is nice and tight and the parts are all pre-machined to have a slight pre load at the bearing. I can tell you mine spin nicely with no free play and a slight amount of drag..just right.
The half shafts I used were from a Mustang Cobra that I shortened. Besides being too long, they were 1 3/4" solid bar stock with the ends machined down to about 1" diameter and splined and grooved for the snap rings. Way too heavy. I cut the ends off, leaving a short amount of the large diameter, then after sizing them and machining a step into the two pieces I pressed them into a length of 1 3/4 OD alloy tube and welded the whole thing like a driveshaft assembly. It is about 1/3 the weight and I was able to hide the welds under the boots. I used a ford inner CV that I adapted, but there is no reason why you can't mix and match to get what you want...If you go with standard size halfshafts I think they are about 1 inch or 1 1/16" diameter and it should be no problem to get those done.
I will post the bearing number this morning when I get in to the shop.
Cheers
Phil

 

[Phil]

Mike:
Went looking in my files after posting:

Bearing: CR-115A (Ford #M-1215-A)
Snap Ring: Ford # N=803955-S
Hub: Ford # M-1109-A

The hub number is the Ford Motorsports number, The aluminum upright on the Mustang is M-5970-A if you need that.
Off to work
Phil

 

[Mike Simard]

Thank you Phil.

It looks like there are no known stub axles to go with these 27 spline hubs. There may be some aftermarket parts of unknown quality but nobody knows the dimensions of the existing "micro stubs" which tells me it's just people selling things made who knows where.

There is one axle, 928, that I've never heard of breaking and that makes it obvious for me. I just have to make new uprights to house the bearing (like a Cobra).

I've raced a big power 928 and know others that have broken gearboxes, clutch inputs, driveshafts but never an axle component. I've broken 2 gearboxes in my racer but never saw an axle problem either.
The 928 uses the 108mm Lobro CVs with 28 spline axles common to the Porsche and offroad world. The early 928s use an outer axle stub instead of one-piece CV so I'll use that.

The Cobra parts could be useful as well and they have the 4.5 bolt pattern as is. I'd had problems sourcing individual CV from those Ford IRS axles. Ford prevented GKN from selling the CVs and I was left using EMPI (Chinese crap) and had one explode at 100mph. I'd trust GKN parts though, if Ford would allow them to be sold. No such crap with Porsche at least.

 

[Phil]

Mike:
Please Post your results when you get everything sorted. I would love to see it.
Thanks
Phil

 

[MikeM]

Thank you Phil.

It looks like there are no known stub axles to go with these 27 spline hubs. There may be some aftermarket parts of unknown quality but nobody knows the dimensions of the existing "micro stubs" which tells me it's just people selling things made who knows where.

There is one axle, 928, that I've never heard of breaking and that makes it obvious for me. I just have to make new uprights to house the bearing (like a Cobra).

I've raced a big power 928 and know others that have broken gearboxes, clutch inputs, driveshafts but never an axle component. I've broken 2 gearboxes in my racer but never saw an axle problem either.
The 928 uses the 108mm Lobro CVs with 28 spline axles common to the Porsche and offroad world. The early 928s use an outer axle stub instead of one-piece CV so I'll use that.

The Cobra parts could be useful as well and they have the 4.5 bolt pattern as is. I'd had problems sourcing individual CV from those Ford IRS axles. Ford prevented GKN from selling the CVs and I was left using EMPI (Chinese crap) and had one explode at 100mph. I'd trust GKN parts though, if Ford would allow them to be sold. No such crap with Porsche at least.

Mike, sorry bump an old thread...is that sales restriction only for the US or a world wide thing?

 

[Mike Simard]

Mike, sorry bump an old thread...is that sales restriction only for the US or a world wide thing?

Good question. Superformance did source individual CVs from GKN and used custom axles. I don't know why they were able to but I was not.

 

[Mike Simard]

Mike:
Please Post your results when you get everything sorted. I would love to see it.
Thanks
Phil

It will be a while before I finish the whole upright but here are the parts I'm using.
The 928 stub axle is a machined forging (!). That's a 928 wheel bearing and I made a titanium hub for a 5x4.5 bolt pattern.

 

[Phil]

Mike, Thats quite a good looking hub. I can tell you that the bearing I am using is almost Identical to yours in appearance, and the only difference with the axles I have is that the outer CV joint is part of the stub shaft...otherwise very similar.
The only pitfall I needed to avoid with those type bearings was to make sure of a good fit in the upright. I need to heat my uprights a bit and push the bearings in ...not really press them but tight nonetheless, and that was modeled after the original fit in the OEM stuff. Once the outer nut is tightened properly the bearing preload is correct, and I have seen these bearings last quite a while in a much heavier application than I am using.
Looking good so far..have you done any mock-up for the upright yet?
Thanks for posting that.
Cheers
Phil