hi i have a 86 bronco. i did the rear drum brakes today and came to find out i had a 85 LTD fullsize rear end in it. i think it came like that from the factory like that to the best of my ability. the first guy who owned it keep great records of this truck and he dosent have a axel swap in it. and i know the guy who had it before me and i know he didn't do it.

Also from working on it i know i have 85 bronco cap and rotor in it. and from my reseach it was built in late 85 so i think i got a lot of left over parts but a axel from a large car just seams wierd has anyone ever heard anything like this before. and do u think i can replace my drums and backer plate to put in true truck brake system on that axel i am thinking its all ford it might be the same mount.

 

You either have a ford 9" or a ford 8.8 rear diff. get us the gear code from the door jam.
8.8 has a diff cover while a 9" has a removable center section.

an LTD rear end wouldnt fit under a bronco, it would be way to narrow.

 

hocman, I'm not really understanding the problem. A 1979 to 2011 Panther chassis (Full-size Ford-Lincoln-Mercury body on frame cars) rear axle assembly is an 8.8", and probably would be wide enough for a Bronco. My Bronco is no wider than any of the many Panther chassis cars I've had. HOWEVER, the Panther rear axle assembly is coil spring, and has the two rear trailing arms on the axle housing tubes, and also has the two side-to-side locating arms up on top of the differential. A Bronco is leaf spring, and has none of that. Different housing.

And Panther chassis rear axle shafts have wheel studs on a 4.5" diameter circle, which is smaller diameter circle than the Bronco. In the Panther early years, both 14" and 15" wheels were available, but by 1983 or so, only 15" wheels were used. That affects brake drum size.

If, for some reason you really believe that somehow you have axle SHAFTS from the Panther, then your wheels would have to have holes on a 4.5" diameter circle. That is easy to measure to prove or disprove the whole idea.

Or maybe you mean something else, and I'm just not getting it.

 

86 should definitely be 8.8 .. I wish I knew more details about what's so weird about your rearend.. is it just the brakes? give us pics or more details, I'm interested.

 

Not necessarily.
My brother's '86 Bronco has a 9" 3.50. It's never been swapped out.

Easiest way to tell:

8.8: Access plate and bolts are on the back of the differential and are on the opposite side of the driveshaft.

9": Access plate and bolts are on the front of the differential and have the drive shaft going through the center of it.