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What happened to front disc rotor "ONLY"???

Bart

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Dec 12, 2001
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Buffalo Gap, Texas
While converting our '69 Sport (Dana 30) to disc brake in the front I can't find just the rotors anywhere. WTHeck? Everyone wants to sell the complete hub/rotor combo. I've checked W.H, and Tom's catalogs as well as Autozone and OReilly's. Those last two have a rotor only but it doesn't fit the oem hub. Inside of the rotor "hat" measures 6.5" The hub has a 7" flat.
Anyone with any ideas that doesn't involve an arm and a leg?
 

thegreatjustino

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As you've found, the OEM disc rotor won't fit the fit the drum hub. So, what good does just the rotor do you?

If you want to retain the drum hubs, use the Wilwood kit which is a bolt on to the OEM drum hubs.
 

DirtDonk

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Regarding the title of the thread, as you found you can buy just a rotor. But as you also found out, it is naturally for a disc brake application, not a drum application.
Ford never had a disc brake Dana 30 under a truck that I ever heard of.
You have a drum hub and Ford used a completely different hub for the later 44 disc applications.

So whether you are using GM brake components (the only option for the Dana 30 using stock parts of course) or Ford parts on a 44 you need a Ford disc hub to run a Ford disc rotor.

Or you can go with Wilwood as Justin said.
Price-wise you probably want stock replacement parts I would think. Plus it sounds like you already started the GM path anyway.
Buy the hub and rotor combo then. You need it.

What else are you sourcing? You already have the 1975 GM calipers and plates?
Hoses?
Spindles?
 
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Bart

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Regarding the title of the thread, as you found you can buy just a rotor. But as you also found out, it is naturally for a disc brake application, not a drum application.
Ford never had a disc brake Dana 30 under a truck that I ever heard of.
You have a drum hub and Ford used a completely different hub for the later 44 disc applications.

So whether you are using GM brake components (the only option for the Dana 30 using stock parts of course) or Ford parts on a 44 you need a Ford disc hub to run a Ford disc rotor.

Or you can go with Wilwood as Justin said.
Price-wise you probably want stock replacement parts I would think. Plus it sounds like you already started the GM path anyway.
Buy the hub and rotor combo then. You need it.

What else are you sourcing? You already have the 1975 GM calipers and plates?
Hoses?
Spindles?
Paul, you missed the whole point of the thread. We have ALL the parts to put Chevy disc brakes on the Dana 30 including the hubs. Problem is there doesn't seem to be a rotor available that will fit on the hub. So a $30 rotor now cost close to $200 each because the only thing available is a complete hub/rotor combination. The rotor only that is available will not fit on the oem 76/77 hub. I took this very Chevy brake system off the '75 EB I bought some years ago in favor of a Ford system because the '75 has a 44. I saved all the parts from the '75 to put on the '69 except the rotors because I reused them on the '75. I "thought" "think" that I have the very same set up on my '66 (Dana 44 and Ford disc) and my '75 (also Dana 44 and Ford Disc). This morning I'm going to pull the wheel off the '75 to see what is going on. Either the rotor only "was" available sometime in the past and not now or I lost my mind (VERY possible) and don't remember putting on the whole Ford hub/rotor combo. The Bubs should be inter-changeable with the only difference being the bolt pattern.
If you have a pair of hubs with a measured flat mounting serface of 6.5" not 7" I'd be interested in that.
 
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brewchief

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The hub goes on the front of the rotor not inside it.

Sent from my SM-T510 using Tapatalk
 
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Bart

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Buffalo Gap, Texas
Well, I just took a front wheel/tire off the '75 and it is the one hub/rotor. I guess I've lost my mind! If someone finds it PLEASE let me know where it is.
The hub goes on the front of the rotor not inside it.

Sent from my SM-T510 using Tapatalk
So does that mean that the studs have to be moved from the hub and installed/replaced into the rotor? It's must be 20 years since I've messed with a D30
 

toddz69

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So does that mean that the studs have to be moved from the hub and installed/replaced into the rotor? It's must be 20 years since I've messed with a D30
To change a rotor, yes, you'll need to pound the studs out of the hub/rotor combo and then re-install them when you put a new rotor onto the hub. Or in your case, it sounds like you have a hub already so you'll need to install the studs when you install the new rotor.

I shudder to think what the shipping on a rotor is these days but JBG has them:

https://shop.broncograveyard.com/Ro...qGPMA3ycVp2jGwizjRE1Tt-LB5x5m1ioaAghoEALw_wcB

Todd Z.
 

brewchief

Sr. Member
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Feb 11, 2007
Messages
871
Are you sure the hubs you have are disc hubs? When parts got swapped around the entire hub and rotor assembly didn't get swapped on and the drum hubs saved?

Rock auto shows a couple of complete assemblys for 75 each right now.

Sent from my SM-T510 using Tapatalk
 

DirtDonk

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Hey Bart, sorry for the misunderstanding.
It wasn’t you though because when I just started to read your first post, I thought that’s what you meant. But the more I read it and reread it, I thought it was because you were trying to fit on a drum hub.
Sorry about the misunderstanding.

But now it sounds like the plot thickens.
Can’t wait to hear the solution.
 

EPB72

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Pleasant Hill, CA
So this is what I remember from doing the GM swap 25 years ago when wrecking yards had parts and no real kits availble,,,,

GM half ton/blazer spindles ,backing plates,and calipers
Ford f150 hubs and rotors early to mid 80's

Now different kits diffrent options ,,,like duffs budget kit that uses the drum hub with some machining to make a rotor fit ,what rotor i dont't know but they sell them..

One other thing the original GM backing plates are made of thicker steel then the new one's made now..
 
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Bart

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Buffalo Gap, Texas
We went back to Autozone with one of the hubs in tow. Laying the rotor on the counter and laying the hub on top of the rotor (instead of through it) we ended up with a casting "nub" that would stop the two from mating together. We finally "bit" the bullet and ordered two complete hub combinations for the $112 that 1sic mentioned. We spent the rest of the day (night til 9:30) replacing the body mounts. 50 year old mounts were FUN to remove even on a lift. We did that in hopes of getting body panels to line up better.
EPB72, I too thought about finding a lathe and removing some edge material for the hub and inside the rotor for them to fit together but was not sure how that would line up with the caliper/brake pads. So, like I said we just ended up biting the bullet and ordering the "for sure" combos.
Son has only two or three months to get this thing done so time is also a factor here.
Thanks to y'all for the information and I'm sure I'll be calling on all y'all again.
 

brewchief

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If the back of the hub wasn't machined then it was in all probability a drum hub.

Sent from my SM-G965U using Tapatalk
 
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Bart

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Buffalo Gap, Texas
If the back of the hub wasn't machined then it was in all probability a drum hub.

Sent from my SM-G965U using Tapatalk
I agree. Looks like the 3 month window I "thought" was a Bronco restoration period has been cut down to 6 weeks. Oh well, looks like I still own 3 Broncos. That until son takes the 69 Sport home. He better watch it. If I finish it I may not want to give it up. :)
 

Rustytruck

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Feb 24, 2002
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order a rotor for a 1978-79 Bronco. that is how i have purchase just rotors but dealing with the studs is just not worth the effort compared to the price for the whole assembly.
 

Pa PITT

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Stephenville TEXAS
As I recall. I got Mega Lucky Auto Zone ... was going to stop handling those Hubs & Rotor combinations . no.2492.. .
& I bought 6 of them ... they had discounted them I gave 24.99 each . That was years ago .
If my memory serves me correct the Hub & Rotor fit's 1980 to 1986 Ford Big Bronco & 1/2 ton pickups.
THEY COME Put together HUB / Rotor & lug bolts. & Both inside races .
Buy them once & your done for ever. Or maybe 100,000 miles anyway..
.... Others are going to disagree with me .. But I'm going to tell you to buy the cheapest D52 Disk pads you can find. Cheap ones will last 30K miles & Cheap one wont make noise... When I did my conversion My PAD ONLY COST ME LIKE $6.00. I'M SURE THEY ARE NOW 20$. bUT BUY THE CHEAP PADS .
...... FOR my credit , for what I've said. I started as a Parts Man in 1967 & had my own Part Store until 1995. & Then I was a Supervisor for the Parts Plus division I bought from. Laster I spent 10 years with Chrysler & about 11 more at a Freightliner Satellite store . Out side sales. 50 years in the parts bus.
 
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Bart

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Buffalo Gap, Texas
Thanks Pa! I don't know if the sheet metal adaptor bracket is bent or what but the set of hub/rotor combo we brought from O'reilly's were such that we could not get the rear pad installed. I removed the combo from my '75 and was able to get the rear pad in okay. Problem turned out that the combo off the '75 would accept the pad but "trying" to install the two jam nuts tightened the rear pad to rotor to the point that it was locked up solid. Fron pad was sloppy loose. Ended up taking everything back to AZ and "O" and ordering the complete correct parts from Tommy! According to "T" there is a difference between a drum spindle and a disc brake spindle. We've had enough wasting so much time. Axle related "should" go in today and brakes when they get here.
Thanks for the come back.
 
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