My chevy disc brake conversion

[Cooter_76]

Next week the girlfriend's going skiing, so I'm taking a few days off from work to spend some quality time with my Bronco. The main goal of this three-day Broncothon is to perform the chevy disc brake conversion. I have a '73 Bronco with Dana 44 front end and a drum/drum non-power setup. For now I'm going to stick with the non-power setup without a proportioning valve.

I started buying parts last week and hope to have most everything purchased before I begin. Here's what I have so far:

Used - from 70-something Chevy K1500, Price: $80
(2) - backing plates
(2) - spindles
(2) - calipers - for cores

New - from Auto Zone for '76 Chevy K1500
(2) - flex hose (from hardline to caliper) Part #77028 - $19.99 ea.
(2) - sets caliper bolts, Part # H5004 - $3.99 ea.
(2) - calipers, Part #C502 - $14.99 ea
(1) - set semi-metallic brake pads , Part #SG052S - $29.99
New - from Auto Zone for '77 Ford Bronco
(2) - hub/rotor assembly w/races, Part #5492 - $24.99 ea
(2) - inner hub seals, Part # 4250 - $4.99 ea
(2) - inner wheel bearing, Part # SET37 - $16.99 ea
(2) - outer wheel bearing, Part # SET45 - $10.49 ea
(1) - master cylinder, Part #M1617 - $15.99 + $10 core
Sill need
(2) - spindle bearing kit
(2) - banjo bolts (to connect calipers to flex hose)
(2) - bolts & fender washers to replace snap ring on outer shaft

I count $248.84 in new parts and $80 used, for a total of $328.84 to date.

Let me know if you notice anything I'm missing, or anything I have but don't need. ;D

I'll followup with pics once I get into it.

 

[RangerRob]

Your missing BEER

Should be a fun project. Might want to take a look at your axles and u-joints while you have everything out. Would be a good time to replace an worn items.

Good Luck!!!

 

[SaddleUp]

It looks like the big price difference was in the calipers and pads. Mine were more like $18 a side for loaded calipers. (I.E. They included the pads) A saved a few dollars on bearings and the master cylinder as well (I haven't paid more than $12 for any of the master cylinders I've had on mine) and took my old one back to get the core returned.

 

[73stallion]

when you buy the calipers they should come with the bolts.

 

[Cooter_76]

when you buy the calipers they should come with the bolts.

I'll check that out when I get home. All I remember seeing is a couple of crush washers in with the calipers.

 

[Skuzzlebutt]

I'm not a chev expert, but it is K5 blazer parts that are used. I didn't think they used the 1500 designation 'til 'bout ten years later.
Be sure this is 1/2 ton hardware your getting 'cause 3/4 ton stuff isn't compatible with the Bronco parts.

I don't know if K5 and K1500 are the same, so double check.

 

[Cooter_76]

I'm not a chev expert, but it is K5 blazer parts that are used. I didn't think they used the 1500 designation 'til 'bout ten years later.
Be sure this is 1/2 ton hardware your getting 'cause 3/4 ton stuff isn't compatible with the Bronco parts.

I don't know if K5 and K1500 are the same, so double check.

You might be right about that. I actually told the parts store I was looking for a 1/2 ton Chevy pickup.

 

[Cooter_76]

Yesterday morning I started this project in earnest.

I found a pair of spindle bearing sets at Napa. Here is a good thread that shows how all the parts in the set go together.
Napa part number BK1 - $14.99 ea.

I wound up having to exchange the master cylinder for the 1977 Bronco for one for a 1976 F250 "Camper Special" because the Bronco MC has ports on the passenger side. I would have known better if I had read this thread first. Autozone didn't recognize the term "Camper Special", but the did have an option for a truck that had two-piston calipers so I went with that and the MC had the ports on the driver's side.
Autozone part number M1779 - $17.99.

Here's a pic of the spindle bearing on the back of the spindle before I tapped it in with a rubber mallet

 

[Broncos n' VWs]

Hey... I'm in the middle of the same project. I have been trying to do a little bit at a time, so this whole disc conversion project will probably be complete this coming week. Everything is pulled apart, it just needs to go back together with the new parts. Post some more pics of the install. Good luck!

 

[Cooter_76]

I had to sandblast the backing plates, then followed up with two coats of etching primer and two coats of Rustoleum hammered finish rattlecan paint.
The spindle and backing plate mounting was straightforward.

I ground the knuckle and the caliper for clearance. It just took a few rounds of test fitting, grinding, repeat to get enough clearance.

 

[Cooter_76]

Last night RangerRob, Willie, and another friend of ours came over to help me torque the hubs in place following the procedure listed in the tech article. We also installed my new WH 2 1/2" coils.
BONUS: RangerRob got bored and started inspecting the tag on my front diff. Turns out I have a limited slip up front as well as the rear!
The last picture was supposed to show the clearance between the caliper and the knuckle, but the angle isn't quite right.

 

[Cooter_76]

The Ford flex hose connected to the axle bracket with a metal clip. The chevy flex hose is threaded for a 5/8" fine threaded (18 pitch) nut. Three different parts stores didn't have the nut, so I wound up finding a castellated nut at Lowes, then I ground the castellated parts off so I would have access to the brake line fitting.
I may have been able to find the correct nut at the Chevy dealership, but by that time I was pretty frustrated and not thinking clearly. %)

 

[Sac '68 sport]

Man your autozone is cheep.
That same rotor and hub assambly is $46.99 on line and at my local store.

 

[Cooter_76]

Man your autozone is cheep.
That same rotor and hub assambly is $46.99 on line and at my local store.

I just checked the website, and you're right. It shows $46.99. Double-checked my receipt: $24.99. Same part number. ?:?

 

[68 Broncoholic]

The cheapy is probably an Import rather than Domestic. Got to watch those guys!

 

[Sac '68 sport]

What size, length and tread is the bolt/fender washer that goes into the end of the axle?

 

[Cooter_76]

7/16" dia, fine thread, 3/4" length. I bought 3/8" fender washers and drilled them out to 1/2". Not sure why it was necessary to buy 3/8" fender washers. I was following the instructions found here.

 

[Cooter_76]

Well, it took almost a month, but I finally wrapped this project up. For weeks I was plagued with an overheating problem in the driver side hub. I checked the following three or four times: brakes dragging, insufficient knuckle/caliper clearance, brake lines kinked, lockout mechanism problem, improperly torqued spindle nuts.....nothing seemed to solve the problem. I removed and reinstalled the front wheel enough times to apply for a job with a NASCAR pit crew.
Finally RangerRob helped me discover that the inside diameter of the outer bearing was too large . The passenger side checked-out fine. I had purchased the right bearings, but one of the boxes was mislabeled.
A quick trip back to Autozone produced the correct bearing.

It's been two weeks since I got the Bronco back on the road. The new brakes stop straight and quick, albeit with very stiff pedal. Time to start researching hydroboost options...

A few helpful tech article links:
ClassicBroncos.com of course
Lonestar Early Bronco Club
Motoman

 

[BG's 68 Bronco]

What M/C do you have?? Is it still drum/drum?

 

[Cooter_76]

What M/C do you have?? Is it still drum/drum?

I went with the '76 F250 Camper Special M/C (disc/drum.) I've been told there are two bore sizes for the Camper Special. I'm not sure which size I have.