• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

Cloning 77 EB Rear Housing

broncochevy

Sr. Member
Joined
Oct 18, 2007
Messages
372
Loc.
Orcutt, CA
I found someone to narrow my f100 rear 9” housing and I am pulling my hair out going over numbers on what measurement to make the housing to accept 77 bronco axles. I have the 11x2 1/4” drum breaks already. I have done a ton of searching on this site and the webs to find no documentation of this happening before. One mentioned getting the shafts I need And measuring the difference between the shaft that came out of the housing and cutting that dimension off the tube on each side. A rather great idea but I haven’t got them and even if I did it would take me a little bit and maybe some fancy measuring. Has anyone ever done this before take a full-size pick up with 9 inch housing and make it except 9 inch early Bronco links axle shafts from a 1977 bronco?
And if so, did they center the center section in other words the 9 inch center chunk, is it centered in between the wheels? This would still offset the pinion, correct?
Last question, what was the final width of the axle housing measured from the outside of the backing plate mounts; the lip where the backing plate bolts to the housing?
Thanks in advance!
 

SteveL

Huge chevy guy
Joined
Jun 24, 2001
Messages
11,609
Loc.
Hawthorne ca
I have an empty 77 housing on the bench. It measures 53 3/8" flange to flange (outside edge) with a tape measure. Not sure what they're charging you but curry housings for the bronco are designed like the 77 for strength but I think have torino ends for exploder disc brakes. If you're closer to wh I think they sell the same housing.
 
OP
OP
B

broncochevy

Sr. Member
Joined
Oct 18, 2007
Messages
372
Loc.
Orcutt, CA
SteveL, thanks for the measurement, I was beginning to wonder if anyone was going to respond. I really appreciate it. I do know about the housing that’s sold from Currie and WH, I would rather buy from WH, think they are priced better, but I most definitely need to buy axles from them, and, well I am cheap. I have this housing already and I just need to buy new ends, and get it narrowed for $200 or close to it. I know it’s better to buy a bronco axle or a new housing, but I already have this truck housing and also a bronco small bearing housing. I figured I cut a fat hog and save a few hundred, realizing it’s not the most desirable, and get the larger center section and use the 32 spline carrier. Trying to be resourceful and still have cash for the other things. There’s going to be a lot more need to haves.
Does the housing you have look to have the carrier “centered” in the housing? Reason I ask is the diner housing from a truck is not.
 

nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
8,605
I tired to get a measurement from my rear end build but our website for that site is down...I think permanently... :( Dang, I had a lot of info on that site...
 

SteveL

Huge chevy guy
Joined
Jun 24, 2001
Messages
11,609
Loc.
Hawthorne ca
Measuring it looks close to equal but I would hate to give you wrong info. Due to welds and stuff it's hard to be exact with a tape measure. Hopefully somebody with more info can chime in. If your buying new axles and housing ends why not upgrade to 31 spline and big bearing ends while you're at it. Shouldn't be much different in price.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,346
And might as well factor in new, relocated spring perches as well.
The full size perches are too wide for the EB springs, and likely at the wrong angle anyway.

Paul
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,346
And new brake lines, since your original lines won't line up with the new location of the vent hole that the full-width axle has, or might have.

For width, I'm pretty sure you can just use your original housing as the model. The main changes in "width" between EB year models is the axle shaft flange offset. The difference in housing widths for the '76 and '77 housings only is likely just in the hundredths of an inch.
The only difference, width-wise from '66 to '75 between standard large and small bearings is the axle shafts was 1/4 inch. Entirely due to flange offset. Or "bearing offset" if that's the more appropriate terminology.

The differences for the '74-'75 "medium duty" (large bearing, small brakes) was an additional 1/8" more bearing offset. Which says to me (correct me if I'm wrong though) that given the same axle shaft overall length, there was 1/8" less spline engagement in the diff.

For '76 and '77, the shafts were 19/100ths and 7/100ths shorter left and right respectively. I suppose you could make your "77" housing a few hundredths narrower just in case, and then if it's too narrow and the axle shafts won't seat fully, you could grind, or cut off a few fractions of the splines to fit.
Kind of haphazard I admit, but one way to gain back some spline engagement in case that's a thing.

If there were notable differences in housing widths over the years I don't remember seeing it in print. It sure would be nice if we could put that list together though.
Maybe anyone with a loose housing that is a known-year model can chime in, like Steve did with his '77 housing, we'd have our database.

Steve, I think a tape measure is actually accurate enough as long as everything is steady.
And as long as you measure in two planes. No matter how the housing is situated, measure top/bottom (or front/back) to allow for any bending, or even the normal toe-in and camber settings. Even solid axles have alignment specs, so if we take two measurements at opposite sides and then average the value we should have as accurate an answer as we're likely to get.
Having every year would be fantastic, but as long as we have '66 to '75 small bearing/small brake, '66-'75 big bearing/big brake, '74 and '75 big bearing/small brake and the '76 and '77, we should have what we need. Then we can keep it posted up in our "little details database" thread.;D

Sound like a good thing?:cool:

Paul
 

68ford

Bronco Guru
Joined
Dec 26, 2004
Messages
2,710
I understand you have some parts already and are trying to save money, but at some point if it's only a little more and you can have better and new, why not? For 850 you can have a brand new housing like you want with the bigger tappered center, full float with all new hardware. Axles which you need and brake rotors. All you need is 35 buck for calipers and you now have a large housing disc brake full floater.

http://9inchfloater.com/CompleteRrEnd/CmplteRrEnd_28_31.htm
 
OP
OP
B

broncochevy

Sr. Member
Joined
Oct 18, 2007
Messages
372
Loc.
Orcutt, CA
That is correct, I do understand the benefits to that. I just bought a d44 that’s going to need some $$ not to mention the $$$ I just spent on it. The housing narrow job, plus axles from WH, is going to me less than half that $850 axle. I’m stubborn too, I am not throwing rocks at anything said here so 68 Ford, no offense intended.
DirtDonk, yes all that sounds like a good idea. There was a member here who is narrowing the truck axle just like mine started the thread put the pictures up and never finished it. At least not in the thread I was reading I think it was boss hug but I’m not entirely sure. I just thought that there would be a little more info around the web not just any Bronco say about the housing with some stuff but maybe people know more than I do and don’t think it’s pertinent information?? Not sure. I think I’ll be talking to you guys soon about axles might be pulling the trigger today I need 31 spline 77 bronco axles.
SteveL, thanks again for the time measuring. It really settles my mind.
 

suckerpunched

Sr. Member
Joined
Aug 24, 2006
Messages
882
you need more info than the the over all width. you cant assume both sides are 3" shorter. l have narrowed at least several over the years and it is easiest to get the new axles and see how much shorter each axle is from the bearing to the end and cut that much out of the housing.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,346
From my records:

1977 EB rear axle shafts - Left side = 27.18" and Right side = 29.68" as measured from outside of wheel flange to the end of the shaft.

Paul
 

rcmbronc

Contributor
Bronco Guru
Joined
Dec 15, 2003
Messages
2,692
Loc.
Tomah WI
I have there rear hubs, snouts and axles on my truck. Great parts awesome guy to work with. Recommend them.
 
Top