2 different 10x1 3/4, 8 3/4 backing plates?

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Dana67Dart

The parts you don't add don't cause you no trouble
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Hi all.

Recently I picked up 2 backing plates and drums from a friend.

Both came off he's car, he switched to BBP and rear disc.

I have not asked him yet and I will.


Have you seen the non tabbed type before. I have 3 identical and 1 oddball.

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I recall reading somewhere that there was a change to the hardware at some point?
 
Hi all.

Recently I picked up 2 backing plates and drums from a friend.

Both came off he's car, he switched to BBP and rear disc.

I have not asked him yet and I will.


Have you seen the non tabbed type before. I have 3 identical and 1 oddball.

View attachment 1716067342

I recall reading somewhere that there was a change to the hardware at some point?
Change in '68 to the tabbed shoes. Changed again in '69 to tabbed shoe and reversed the adjusters for the new self-adjusting mechanism.
Look in the the MTSC and the shop manuals to see which plates match the ones you got.
The piston retaining tabs should be pretty easy to pick out in the photos.
 
Well crap...

Looks like I have 3-69 (maybe 68) up and 1 - 67

Looking at rock auto the same cylinders are used all 3 years


Anyone know if I can use 67 hardware and shoes on 69 backing plates?


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Dana this is the first I've had someone point out difference in nom 1.75 x 10 backing plates.
I switched my '67 over to '69 hardware and shoes. AFAIK that (the adjuster hardware) is the only thing that needs to be consistant. You can even get away with the 331 shoe frame on an earlier system, although I've had part store guys say the 'Ford' shoe, 151?, is a better match.


Now I'm the one who doesn't remember. But I guess there was a change in the brake cylinders, and the backing plate with tabs maybe related or is just a way to rpevent the pistons from coming out. Someone here will know.
 
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In the 69 FSM it calls the tabs piston stops.

I have a full set of the 69 up type.

But I would rather have all correct for 67 so down the road i don't have to remember what goes with what.
 
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I've never had a problem using hardware kits from other years (usually a later kit on an earlier car), but, I haven't done every combination. I just made sure to use everything from a particular year so, shoes, hardware, and hydraulics match. I believe all the holes and anchors are in the same place.
 
Looking at part numbers on rockauto, shoes are unchanged from 64-72. Brake adjusters change in 68 or 69. This means any adjuster kit will work on any backing plate/shoe. Ford 10 x 1 3/4 shoes are identical ( I’ve laid them next to each other) to the 68 and earlier. In fact the adjuster parts and springs are mostly the same. I will attach photos of the assemblies.
 
Looking at part numbers on rockauto, shoes are unchanged from 64-72.
Its another case of one size will fit close enough that most buyers won't know.
Those are 331 shoes introduced in '69. You might want to knock the pin out to be sure it doesn't interfere.
1968 used FMSI frame number 288; 1967 and earlier used 256, although the Ford 151 is very close.
Do the slight differences in the holes make a difference? Chrysler says yes. The aftermarket says no. I say everyone can make their own choices.
I've used 151 (from a local relining thats now out of business) with the earlier system and was satisfied.
More certain is the lining materials can make difference in some situations - and that's even more difficult to get info on. But all lining manufactures will provide the edge code friction rating. So thats at least a clue.

These are 288 shoes.

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Brake adjusters change in 68 or 69
1969.
This information is all available in the Master Technician Conference booklets, and also the shop manuals, etc.
Between Imperialclub, mymopar, and Hamtramck historical on-line websites we now have incredible access to original material that were formerly at dealerships.

Shoes
256 through Feb 1967
288 Starting March 1 1967. Hardware is the same as before. Only difference is the 288 shoe had tabbed contact points (as seen above).
331 Starting with the 1969 Model Year. Must be used with new automatic adjuster system.

Adjuster Systems.
Through 1968 Model Year auto-adjusters push down on the star wheel.
Starting 1969 Model Year, auto-adjusters push up on star wheels. Star-wheel Adjusters expand in opposite direction from earlier system.
 
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Thanks for clarifying the shoes. I don’t have the references you do. Don’t know the depth of knowledge the OP was asking for but that’s helped me out
 
The 67 would be the same as the 68
Interestingly the 68 parts book lists the same part numbers as the 69 parts book for the backing plates.

Maybe it was a mid year 68 change????
 
Don’t know the depth of knowledge the OP was asking for but that’s helped me out
It is all good info.

Luckily I have it all sorfted out now.

I now have 2 sets of 69 up with piston stop tab backing plates and 1 set of 67 (maybe into 68???) No piston stop backing plates.

Since my 8 3/4 is going into my 67 Dart I'm using the push down adjuster and the no piston stop backing plates. Just easier to keep everything 67.

But wow what a education, and on a fluke that my friends (I learned it was a wrecking yard aquired rear) had one of each backing plates on it.


All of my experience with drum brakes has been with the push down adjuster style brakes.


I looked at the Ford backing plates to see if they looked the same, ( bolt holes would be diferent for sure) and they are not the same stamping.
 
Very hard to know unless you go into the references mentioned by Mattax and narrow down the part number change and when those parts were supplied to production. For most guys purpose it really doesn’t matter. I like to do like the OP and make the parts match the parts books so I know what to look for long after I forgot what I did.
But not to down play the value of that kind of information. Guys with original GTS darts really want the right parts to maintain the cars value. The dates provided for shoes are a good hint of when redesigned parts were put into production.
One last comment about shoes and aftermarket. Most suppliers will make a shoe that covers as many models as they can. Safely. So a shoe designed as a”331”
 
331 would be backwards compatible to 68 and 67.
I have another small rear detail that is sometimes overlooked. Around the time the backing plates changed, the location of the vent changed as well. I will attach photos shortly
 
Here is the later housing. The vent is located about 6 inches further down the tube and tilted toward the back. This becomes major issue when selecting the right flex hose for the brakes.

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And as for the Phord vs Mopar backing plates I have a pair of Phord that I was going to measure and compare to the Mopar. Mount Holes can be redrilled to mount it to the Mopar housing and the “green bearings” are definitely not Mopar.
I’m also going to compare to a Jeep backing plate…
All an up coming tech article I will post.
 
Part searching is such an education.

I have learned so much that I didn't just 2 months ago.

I also stumbled on the patents for how the housings are made.

Confirming my assumptions

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