I have two complete 9" rear ends, one a 64 with 3.89 gears and one a 77 with 3.25 gears. Two questions, will the newer pumpkin work in the older housing and will the bigger drum brakes on the 77 work on the older 64 housing? It looks like the 77 drums would work if I use the 77 backing plates. I think that both rear ends have 31 spline axles or at least they are mared the same. Any help would be appreciated. I know that this is probably the wrong form but the rear end is going into my 48 F1

 

I dont tag myself as a 9" guru but Ihave done quite a bit of work with them.

Question #1-will the newer pumpkin work in the older housing? Yes, same bolt pattern. 28 or 31 spline center sections use the same bolt pattern for the pumpkin, 31 spline axles are larger in diameter and use a larger wheel bearing than most 28 spline axles.

Question #2-will the bigger drum brakes on the 77 work on the older 64 housing? Maybe, depends on wheel bearing size. If both housings are small bearing or if both are big bearing then yes. You must do a full swap though, backing plates, shoes, hardware, and drums.

If one housing is small bearing and the other is big bearing it wont work. The 4 "T" bolts have a different spacing for big and small bearing and the backing plates are not interchangeable.

You could always convert to rear disc in either case, by the time you rebuild all of your rear brakes with shoes, hardware, drums etc... a rear disc conversion isnt that much more to get all new parts with E-brake provisions. If you dont care about a rear ebrake then the kit is probably around the same price for drums or rear discs.

Hope this helps!

 

Thanks for your help. It appears that the T bolt spacing looks to be the same on both rear ends. The reason that I want to use the 77 brake parts is that they are almost new, so the price is right. I am going with disc in the front, probably the kit from Speedway but not sure just yet. I am also going to try and install a Fox Mustang pedal box and use the Mustang firewall booster. We will start tearing rear ends apart this weekend.

I think that going with the 3.25 gears and an AOD should make a nice highway cruiser.

 

Out of a '64...what?

Out of a '77...what?

Your pumpkin may not be able to be swapped. A lot of the earlier carriers had no provisions for the oil fill because they were located in the housing. Vice-versa for the later carriers/housings. Wrong combo will result in not being able to add fluid into the axle housing.

Also bearing backspace (distance from the face of the wheel bearing to the wheel mounting face of the axle itself) is different between different 9" axles. This will affect how your drums sit and align to the brake shoes. Simply swapping the backing plates may not be enough as Ford engineers "Had a Better Idea"... I just wish someone would have told them to USE it.

I've come to find out that not all 9" rears are created equal and that mixing and matching parts can be a bit difficult and could result in big problems if not properly researched.

 

Both rear ends are out of 1/2 ton trucks and you are right about the fill holes, the 64 is in the housing and the later is in the pumkin. I am learning a little bit more about these rear ends every day. I am fimiliar with the Mustang rear ends which are easy, 28 spline axles have an hour glass on the end and 31 spline have the two dimples, I guess truck axles a different, the early 28 spline axles may have the dimple on the end. I may have 28 spline axles in the 64 truck rear end, which may be OK since I have two 28 spline pumkins here in the shop a 3.00 open and a 3.50 Eaton Locker. I guess that I will just have to pull things apart to find out what I got. Same thing with the brakes I will just pull thing apart and start measuring.

 

Yeah you'll find that most the truck stuff is 28 spline up until the mid-70s. Then 31 spline stuff starts showing up more regularly. When you tear into your axles, just be sure to measure, measure, measure. Ford did some weird stuff between all those years of the 9". I can tell you right now I'm pretty confident the brake assemblies won't work right from the '77 axle to the '64 axle. That bearing backspacing on the axle shaft itself is going to be the culprit. Why not just run the '64 axle as is? It should be the correct width. I know you said the brakes were new on the '77 axle, but you'll see once you start measuring and swapping.

 

Looks like the 77 brakes won't fit, the axle offset is not the same. I am looking at about $200.00 to completely rebuild the drum brakes with new everything. Where can I get a disk brake conversion for anything close to that amount?

 

I bought mine for $400 at a local speed shop, that included rear E-Brake provisions though. He said if I didnt want the E Brake It would be around $300.

Without E Brake- $310 to your door

Right Stuff ZDCRDM1 Ford 9" Rear Disc Brake Conversion Kit | eBay

With E Brake- $369 to your door

Ford 9" Rear Disc Brake Conversion Kit Small Bearing | eBay

This is the kit I used
With E Brake, Braided Stainless Hoses, Drilled and Slotted Rotors $400 to your door

http://www.ebay.com/itm/Ford-9-Unive...9bc17c&vxp=mtr

 

I gave Right Stuff a call. These kits would work fine if I had a car rear end and could use a 5x4.5 lug pattern. They don't make a truck axle setup for the 5x5.5 lug pattern and other than Classic Haulers, at $600 for the kit, I don't know who does. Thanks for the help.

 

Might give more consideration to a 3.50 than getting married to the 3.25 - I got a 3.00 and dislike it. I scoured here more and more threads for opinions - seems 3.50 is the preferred, and 3.70 is for those who want a touch more acceleration and less downshifting on hills. A '48 flat brick wall face is gonna be hard to get above or handle beyond 75 mph. I am currently looking for a 3.50 locker center section myself.


Any interest in getting rid of that 3.50 locker center section?

At a junkyard I found a complete rear end drum to drum for $89.99 (plus tax title, license, dealer, delivery, core and enviromental) - total out the door is $150 ish. Might rather than try real hard to upgrade or fix what you got, head to the yard and look for a new donor - gonna suggest 3.50, see #1 above. West of the Miss. your prices should be similar, they scalp those boys back east.

I think the 64 wouldn't have self adjusters, yet another reason to go find a '72 or such in a yard.

The target you are looking for btw is 57-72 ford 1/2 ton truck (for correct width), newer than (guess) 68 for self adjusting better brakes. I have a spreadsheet of some ideal 's if you want it.


My ideal, would be found in a 69-72 1/2 ton with tag starting WFE-C (3.50 locker) , or a 69-72 1/2 ton starting with WFE-A (3.70 locker).

 

Summit racing carries several rear end disc brake conversions. Currie is one they carry that can get you any bolt battern and back spacing you need.

 

Here is a link on doing it yourself:

https://www.ford-trucks.com/forums/8...sion-help.html

and a little more:

Ford 9" Disc Brake Conversion

 

That stinks... was afraid that was gonna be the case. Why the sudden urge to go rear disc? Spending $200 to rebuild the entire brake system seems a bit high, but it might not be if you are getting new drums too. Any used rear disc rear end will likely need to be gone through or at least new pads and rotors. Most bolt-on kits for the 9" are definitely more than $200. If your desire is to have auto-adjusting rear brakes, robbing the backing plates drums and parts from a '67 or older application should give you that option, bolt-on. The 68-up models used a wider shoe and I'm not sure if the bearing offset is the same or not. (to allow a swap of '68-'72 parts onto the '64 housing) The '67 axle used the same shoe size as all the '57-67 axles. I do not know when automatic adjusters were introduced. Could be '65 or '66 but I do know the '67s are auto adjust.

 

1957/67 F100's have 28 spline axle shafts: B7TZ-4234-A / R/L is the same / Rear brakes are 11" x 1 3/4." *

1968/72 F100: There are two different 9" rear axles. One has 28 spline axle shafts, the other has a 9 3/8" ring gear and 31 spline axle shafts.

C8TZ-4234-A = 28 spline axle shaft / R/L is the same.

C8TZ-4234-B = 31 spline axle shaft / R/L is the same.

9 vs 9 3/8: Only FIVE parts are the same: Housing gasket, pinion seal, one pinion bearing and cup, pilot bearing retainer.

EVERYTHING else is different!

1973/79 F100 & 1975/79 F150: Some have 28 spline axle shafts, some have 31 spline axle shafts, as it depends on the applications.

There are six different part numbers for the 28 spline axle shafts, six for 31 spline axle shafts, I kid you not.

Without the Ford axle ID tag, it's a PITA figuring out which axle shaft is correct! Most peeps are unaware how FoMoCo measures axle shaft lengths.

And, be aware that some 1980/83 F100's have 5 lug wheels on a 4.50" bolt circle, some have 5 lug wheels on a 5.50" bolt circle.

Passenger Cars wheels with a 4.50" bolt circle will not clear the calipers on the F100's 4.50" bolt circle.

Other than these oddball 1980/83 F100's, all other F100's have 5 lug wheels on the 5.50" bolt circle as do 1966/96 Bronco's, 1975/96 F150's, 1975/2012 E150's.

* 1968/79 F100's have 11" x 2 1/4" rear brakes, as do: 1975/96 F150's, 1978/96 Bronco's / Some 1980/83 F100's have 11" x 2 1/4" rear brakes. Some have 10" x 2 1/2" rear brakes.

 

I already had it online, so I'll link here - some donors to choose from for ideas (no info on brakes though, just sizes, applications, spline, tag number etc)

http://www.brainsbivouac.com/cars/1948/Tech/Ford 9 inch Rear Axle Master Database.xls