Ok, I give up. I'm trying to find replacement rear axles for an old truck I'm restoring, but the rear end isn't the original and I have no idea what it's out of. The axle shafts are 30" longe, 28 spline, but I don't know to reference the axle bearing inside diameter.

I found replacement Moser axles from Summit that even their rep thought was correct. It was the same length, number of splines, and 5x4.5 bolt pattern which is what I want, but the bearings didn't fit, the inside diameter was too small so I returned them. The axles I have now are 5x5.25" but I need 5x4.5 to fit a rear disc brake kit I have, that's why I'm replacing them. I'll attach a few pics and hopefully someone can ID this bugger.

Also, I "think" this rear end is from a late 60s to early 70s vehicle, that's why I'm posting here, but I could be completely wrong (an probably am). So please kick me to the right forum if needed.

Thanks in advance!!!!!!
Brian


Here's the rear end



"Big Ford" flange


This is a C7AW-E case based on the rib depicted on the other image





This matches what I've got

 

The 3rd member is out of a Ford passenger car, as denoted by the cast-in 'hood' sticking out over the driving pinion/companion flange.

 

Thanks Steve, any idea how to tell what model and year (or range)?

Hopefully this doesn't mean I'm getting booted from the "Truck" forum!

 

Passenger car 9's have right and left specific axle shafts, the right axle shaft is longer than the left.

I will need to know exactly how long each axle shaft is, to 'pin down' what it's from.

Here's a pic from the truck parts catalog showing how Ford measures the length of axle shafts.

 

As far as I know, '67 and earlier Ford truck 9-inch rear end housings and axles are a little narrower than '68-'72. Hard to tell exactly what rear end housing you have from the photo.

There is no direct bolt-on disc brake setup, using later factory parts. However, if you're going to install rear discs on the rear of a Bumpside, probably the best thing to do is locate an '80-'83 F100 9-inch rear with the factory 5 x 4.5" lug pattern (some '80-'83 F100 9-inch rears did have the more common 5 x 5.5" pattern so you would need to verify the lug spacing).

Once you had this rear end, the spring perches and lower shock mounts would need to be located 2" more inboard (per side). After that, a pair of axle spacer rings from Currie Enterprises and a set of '95-'01 Explorer rear disc brake assemblies would bolt onto the Bullnose housing.

On the front, if you have Dentside F100/F150 front discs, you would need to have the O.D. of the rotor hubs turned down and the lug pattern redrilled for 5 x 4.5" lug spacing.

This particular Bullnose 9-inch rear end will have a 4 bolt 'Torino' large axle bearing end flange pattern of 3.56" x 2.00" (same backing plate bolt pattern as on the '95-'01 Explorer rear discs) vs the old large axle bearing flange pattern of 3.50" x 2.375." The Bullnose 9-inch rear end will also have 31-spline axles.

 

Any Ford 9-inch 3rd member (passenger car or truck) will fit in any 9-inch rear end housing. The only limitation is the number of splines on the differential. The axle spline count has to match the number of splines of the differential and the axle length has to be compatible with the housing they are being used in.

 

A - Looks to be about 29-3/4", so 29-11/16" could be correct
B - Measured about 1-3/16", so I'm guessing 1-1/4" is correct
Splines = 28
C - Measured about 7" but it's probably 7-1/16 since I wasn't able to put the tape measure up against it
D - 5-1/2"? Mine is almost exactly 5-1/4" from center to center measuring two bolts apart
E - 5 lug

This looks to be the one if it wasn't for the bolt pattern

 

So as long as the length is correct, the spline count is correct, and the bearings fit the axle and the housing, then it should work? If that's the case, I should be able to just have one custom cut.

 

5 lug wheel stud spacing is measured from the center of one wheel stud to the far side of an opposing stud. Not center-to-center.

 

The thing is, the OP wants to know what the 9 is from. The only way to find this out since the ID tag is missing, is to measure the length of both axle shafts.

The other thing is, there are two different sizes of ball type axle bearings (large & medium).

If from a 1974/79, could have either a tapered roller bearing/seal combination or either of these ball bearings w/a separate seal.

Some passenger car wheels w/9's have either the 4.50" or 5.00" bolt circle pattern. No cars w/a 9" have a 5.25" or 5.50" bolt circle pattern.

 

Ford truck 9-inch rear end leaf spring perches will be mounted on top of the axle tubes. Ford car 9-inch leaf spring perches will be on the bottom side of the axle housing tube --if it was a 9-inch housing from a passenger car with a coil sprung rear end, the coil spring perches would be an immediate give away that is wasn't a housing from a truck.

If the width of the 9-inch rear end housing is over 56" (from the back side of one drum backing plate to the back side of the other backing plate), then you would know it isn't from a Bumpside but would have to be from either a Dentside or a Bullnose.

 

Both axle shafts are the same length, 29-3/4".

The bearings aren't tapered and they're sealed, O.D. is 3-3/16".

And it is a 5-1/2" bolt pattern, I was measuring center to center when I posted that it was 5-1/4".

 

Given the length of the axles, they would be too short to fit in a Dentside/Bullnose 9-inch housing. The housing and axles would appear to be from a Bumpside with a Ford passenger car 9-inch 3rd member. The car 3rd members are generally high geared. If that 3rd member still has the stock passenger car ratio in it, it's likely to be in the 2.75 to 3.00:1 ratio range.

 

B7TZ-4234-A (replaced B7C-4234-A) .. 28 Spline 9" Axle Shaft - 29 11/16" long - R/L same / Uses large ball bearing / Obsolete

1957/67 F100.

Note: This is the 10th entry in column left of the pic in post #6.