I'm trying to find a "kit" to convert my 1970 F100 9" rear from
drum to disc brakes.

I thought I could use the Ford Racing Performance Parts kit #M-3200-G
but it will NOT fit my Early Big Ford 2.375" X 3.56" big-bearing (3.15") axle flange.

Anyone run in to this issue tryin' to go the disc route?


-Thanks in advance...

 

Jeff's Bronco Graveyard has various kits for trucks and broncos with 9" rears from 66-86 might give them a call they could have something for you.
-Johnboy

 

$99 dollar disc brake upgrade!
Been doing them for years..............

Chevy caliper brackets (Blazer)- junkyard- $15.00 for both
Chevy calipers (78- 1/2 ton) Autozone- $13.99 each
Pads (same) Autozone- $7.99/ set
Ford rotors (78- 1/2 ton) Autozone- $23.99 ea.

Total $99


Keep in mind that a spacer or new bearing retainer plate will have to be made, but Currie carries them. Also brake lines will have to be added, and were left out of the price. These were left out intentially, because this would put the cost over $99.00 and that would not sound as cool.

 

Johnboy...man...I completely forgot about that place!

Thanks man...OH...NICE Browning A5!!!

 

75F350...GREAT...right now I'm workin' with an empty axle housing on my
fab table so anything is possible...

Waiting for "small parts" to show up to start on the center section...

Picked up a Ford Racing Performance Products M-4204-F28A diff from
a local dealer the other day so I'm gettin' closer...

Thanks for info man...
-

 

In this picture...the calipers you use in your disc brake conversions...are they what you would call the "'78 and later D154-type GM Brake Caliper" ?

-

 

The caliper is just a run of the mill chevy 1/2 ton front caliper. Find the caliper that fits the bracket, thats the idea anyway. For a ford, just use a ford rotor, and not the chevy rotor, and you have what you need.
The option here would be to use an El Dorado rear caliper if you must have an emergency brake.
Take the caliper bracket to the parts store and use the bracket as reference.
These calipers were the same for many years. You almost cant get the wrong ones.
Keep in mind that the Chevy caliper bracket is .250" thick and the stock ford drum brake bracket being replaced is .150" thick, One will need a .100" thick spacer between the retainer plate and the axle seal to keep the axle from moving back and forth .100". Currie actually has these new retainer pre made and available for purchase.
After a small bit of grinding, and matching the holes from the caliper mount and the axle housing, you will have a disc brake equiped rear axle.

 

OK...just checkin'...here is why...what do ya think...

The only reason I asked is 'cause...the independent front suspension
I'm installin' on this '56 Effie came with front disc brakes and use the
D154-type GM Brake Caliper shown in your photo...

Man...was I supprised when I opened up THAT box...

So I figured IF I could find a way to use the same calipers
and pads...and maybe even the same rotors... on the REAR...
I'd have less part numbers to keep track of on the shelf...

Just a thought...the brake gap I started with is 2.5"...

I got some simple engineering to do but ya pointed me
in the right direction...

Not sure about the e-brake...I'm goin' with an automatic
so that might simplfy things a bit...


-Thanks...I keep ya posted...

 

Well, to be street legal (and safe), you need an emergency brake.

Also the fact that steep hill parking is not kind to the parking lever in auto transmissions and if the force is high enough, you might not be able to shift it out if gear, so you would have to apply the "E" brake to prevent this.

The E4OD used in the early super duty had a parking brake on the back of the trans as the truck had 4 wheel disc brakes and used non-parking brake rear calipers.

Also, some street rods used a disc brake installed on the input of the rear end by the u-joint and a mechanical caliper.

 

I hear ya, and agree that running the same parts will at least limit the troubles when you run to the local parts store and ask for some brake pads.
Kid with pimples barely out of high school asks:
"Hey there, welcome to (favorite parts store), how can I help you?
You as the customer:
Yeah, I need some brake pads for my old ford out there.
Pimple kid:
"Sure what year is that?"
You as the customer:
Its a 56.
Pimple kid:
"Sure is nice, (as he types in the old computer), you said brake pads, but my puter shows only brake shoes are available, thats what you meant right? Front shoes or rear?"
The rest gets better, and keeping parts simple is the way to go.

Heak, you should see when I go into a parts store. I have to bring a list of all of the donor vehicles used just to get some stuff together.
They usually want to know if I have a shop and will be working in all of those vehicles in one day. I usually get some funny looks when I explain that I need ford front brake pads for a 79 1 ton 4x4, 78 front pads for a 1/2 ton chebby that I will use for the rear, spring bushings for a toyota, radiator mount bushings for a late model silverado, a seal kit for a 70's dodge motorhome steering box (saginaw), (I could go on for a while, but you get the idea) and then try to explain that all of these parts are for the same truck!

It gets interesting, and keeping data on everything can get a little tedious.

Back to the topic. I believe that using the same front rotor might be a little difficult.
I believe that the IFS rotor really cant be used. I recall the hub design is not even close. Is the 2wd rotor integrated with the hud itself? I dont see how an axle would pass through a 2wd rotor.
I also believe that the offset in the rotor itself is different.
This is why the 4wd front rotor is being used in the rear. It has to mate directly flat against the axle flange. Also consider the relationship between the caliper bracket and the location of the pitch line of the rotor.
What do I know? Nothing I guess, but this sure is fun. I have a good time with it. Building this kind of stuff anyway.
Here is a shot of the junk with the caliper and rotor removed:

 

That clears that up...a little...uuhhhh....

Tell me again what that caliper bracket is off of...please...

THAT picture cleared up a few questions...

Gettin' closer...

 

....yeah...hadn’t really thought of that...

Thanks...

 

CAliper brackets are off of a 1/2 ton 4wd chevy truck or blazer. These are the front caliper brackets for a 4wd axle.

 

...only had to re-read the whole thread about 10 times...

Thanks man...

 

Why not use the 78 rotors with the hardware from a 9" car axle and stay all ford?