Bronco 9" swap

[brianproctorla]

I am considering swapping in a 66 ford Bronco 9" limited slip rearend into my 65 mustang.
I have read through a few posts regarding this swap, but I still have a few questions.

1. The axles have the 5.5, truck, bolt pattern, so that is a problem.
If I redrill the correct bolt pattern, will the larger axle flange impact my choice of brakes?

2. The axle sizes are 27.25 Left and 29 5/8 right (28 spline). If I get new axles, I think I could use a 93-97 or 99-2001 ranger axle for one side (27 1/4) and perhaps a 79 - 86 mustang (29 1/4) or a 94-98 mustang (29 15/16) for the other side. These axles will be from a 7.5 or 8.8 rear. Should I take into account the c-clip groove? i.e should I cut off the c-clip area of the axles. If so, I will need to consider slightly longer axles to compensate for the length I am going to have to cut.

3. The different axle lengths reflect the pinion offset. Will this offset cause any problems as far as clearance?

I understand that the perches are on the wrong side of the housing and will need to be relocated.

The housing is almost exactly the same width of a 65 rear and this housing has the small bearings, so that is a plus.

 

[rbohm]

first compare the axles from your mustangs current rear end to the bronco's. if your mustang has an 8" rear, the splines and axle size are the same. the length might be different though. as for the pinion offset, depending on how much you might have problems with tunnel clearance. if you cant use the axles from your 8", go ahead and use the bronco axles, change the wheel bolt pattern, and machine down the flange to fit what ever brakes you plan to use.

 

[brianproctorla]

Thanks for the help.
I currently have a 6 cyl, 4 lug, rear, so I can't use the axles.
The
I have a 67 , 8 inch, rare, I originally planned on using.
The axle lengths for the 67 are 27.125 and 31.250, so I might be able to use one of the 67 axles.

If an 8.8 axle is used in a 9 inch housing, does the c-clip end have to be eliminated from the axle? How long is the c-clip section?

 

[96 DOHC Cobra]

You can't use an 8.8 axle in a 9" rear. They're not machined to hold a wheel bearing.

 

[brianproctorla]

Thanks.
That really helps me out.
That means that I can only use 28 spline axles from an 8 or 9 inch correct?
(the pumpkin is 28 spline)

 

[65ShelbyClone]

That means that I can only use 28 spline axles from an 8 or 9 inch correct?
(the pumpkin is 28 spline)

Yes. The 8.8s have the bearing mounted in the differential housing and retained with C-clips in the diff whereas the 8" and 9" has them pressed onto the axle and held in with plates behind the brakes.

Oh the irony! I have a '57 Ford passenger car 9" under my '68 which is the same width as '64.5-66 rears. On the other hand, my old man just cut and modified a '68 Cougar 9" which would have fit under my car just like stock. Even uses the same brakes.

You could get the Bronco 9" housing narrowed to the '65-66 spec and use your 8" brakes/axles, or you can try to find another rear end. Just double check all measurements. Years ago I found a '67-68 rear under a '65 Mustang I bought and didn't know the rear was too wide.

 

[brianproctorla]

I appreciate the help.
The 8" rear is a 67 mustang rear, so it is going to be too wide.
I could use one of the 67 mustang axles in the bronco, I believe.

I could have the bronco axles re-drilled for a 4.5 bolt pattern at $100 a piece.

I think I could use a 30.125 axle from a 64-66 mustang for the other side (which should be 29 5/8).
I have a 64 axle, but it is 4-lug.