What was the "improvement" from '68 to '69 drum brakes?

[moparedtn]

Most of the parts listings (new or old) make the differentiation between these
two model years when it comes to the front and rear drum brakes on these b-bodies.

Although both are obviously the same ol' Bendix-designed setups, the only
difference I can notice when looking in the FSM's is in the self-adjuster setups -
'68 uses the spring to hold the adjuster wheel from spinning, while the '69 has the
familiar hook and eye cable design.

Is that the only difference in the two years or are there more "improvements"?
I'm going to rebuild my '68 GTX's brakes stem to stern and I will use all USA made
parts and this is the only real question in all that for me.

 

[F4R/T]

Asbestos linings or not Ed?

 

[moparedtn]

Asbestos linings or not Ed?

Absolutely.

 

[F4R/T]

I shy away from them , just be safe when using them.. my dad has asbestosis.. I went with semi metallic which I’m not sure is much better in reality.

 

[moparedtn]

I shy away from them , just be safe when using them.. my dad has asbestosis.. I went with semi metallic which I’m not sure is much better in reality.

I'm very sorry to hear of your dads' illness. :-(
It took the industry decades to come up with a better substitute for asbestos - and honestly, I still don't think
they have (carbon metallics certainly bite better, but now we routinely replace rotors as a result and they're noisy).
I know the factory stuff worked well and I want that original feel to these again; if anything else, it's a challenge
to achieve, anyways.

 

[Ironbuilt]

I'm very sorry to hear of your dads' illness. :-(
It took the industry decades to come up with a better substitute for asbestos - and honestly, I still don't think
they have (carbon metallics certainly bite better, but now we routinely replace rotors as a result and they're noisy).
I know the factory stuff worked well and I want that original feel to these again; if anything else, it's a challenge
to achieve, anyways.

I agree Ed, the industry is still searching for a "better" option than asbestos. You are a smart man, don't put your face in the drum when removing them, and use care when adjusting. Other than that, replace with asbestos and enjoy. One set of brakes will last you the life of the car.
Oh yeah, and post up some pictures of your endeavor.

 

[33 IMP]

I am NOT sure, but i think my 69 does not have self adjusters. 11x3 fronts,11x2 1/2 on the dana in rear.

 

[moparedtn]

I'm sure I'm not alone here, but when I think of how many years I'd get up to my elbows in brake dust
(breathing it too, of course) just doing brake jobs on old cars - whew, who knew?

I never did them for a living, daily - but for my own cars, relatives' cars, friends of relatives' cars....
well, when you're the mechanically declined fella, folks just seemed to come out of the woodwork
wanting you to work on theirs, too.
Y'all know how it is.
I'd hose everything down with Brakleen (including myself, before a final wash with Gojo) and make it
all go away, but I can remember the smell of asbestos brakes very well - which means I huffed my fair
share of dust.

 

[moparedtn]

I am NOT sure, but i think my 69 does not have self adjusters. 11x3 fronts,11x2 1/2 on the dana in rear.

Depends....what do you have, exactly?

 

[33 IMP]

Depends....what do you have, exactly?

69 A12 runner.
Still fiddling with a brake problem on my 62, 10" brakes, and it does have self adjusters. I just havent had to do brakes on my runner in a long time.

 

[Billccm]

Consider musclecarbrakes.com
Friend has them on his chevelle and I drove it with manual drums. Not as good as a Dr Diff conversion, but improved over stock drums.
I'm sure @Dennis H Will tell you about his brakes.

 

[moparedtn]

Consider musclecarbrakes.com
Friend has them on his chevelle and I drove it with manual drums. Not as good as a Dr Diff conversion, but improved over stock drums.
I'm sure @Dennis H Will tell you about his brakes.

Oh trust me, I have. In fact, that was the route I was going to go....
but that's a darn expensive trip, too.

 

[Billccm]

Yep it's about 20% more than a Dr Diff disc conversion. I had a difficult time deciding what to do for my road runner.
Very happy with the Dr Diff brakes, but the road to conversion was not easy for me.
Next car that comes along I may just do the musclecarbrakes.com

 

[moparedtn]

69 A12 runner.
Still fiddling with a brake problem on my 62, 10" brakes, and it does have self adjusters. I just haven't had to do brakes on my runner in a long time.

Y'know, having adjusters just may be what the "improvement" is, at least according to Professor Ehrenberg...

I'm pretty sure my '68 GTX has this set-up (or similar) - it's fairly easy to spin the adjusters from behind
using a flat blade:

The spring is what holds the adjuster in place by friction pretty much...

To quote Rick: "The adjusters were totally redesigned for '69, no more over-adjustment. WAY better."
I don't know which one in my case, but he must mean like this:

Or maybe this?


I need to do some more research, obviously....

 

[moparedtn]

Nobody else have any input on this? Ok... I'll just post this for my own edification then.

From the 1968 Factory Service Manual:
"The new models have a self-adjusting servo contact, two shoe, internal expanding brake.
The lower ends of the brake shoes are connected by a tubular star wheel adjusting screw (fig. 1).
Police cars with heavy-duty brakes are not self-adjusting."
This would appear to indicate that all '68's had self-adjusting brakes except cop cars?

Also from the '68 FSM, here's the illustration of 10-11" drum brake hardware/installation:

The rears look just like these, too...
I reckon that solves that - the '68's had self-adjusters, just not the kind with the spring-loaded gizmo on the end of the adjusting cable.

 

[glen e gates]

when you work with asbestos brake shoes wet them down first that will settle the dust use soapy water then you can use aerosol brake cleaner wont be blowing the dust all over you

 

[moparedtn]

when you work with asbestos brake shoes wet them down first that will settle the dust use soapy water then you can use aerosol brake cleaner wont be blowing the dust all over you

Thanks, good tips. On this one though, there isn't any chance of asbestos linings either being removed or
installed, unfortunately.

 

[moparedtn]

Update:
All parts have been sourced and paid for and are in some part of the shipping process now....
and I managed to keep it "Made in USA" in the process as much as possible.
I have stuff coming from several sources, including Central Jersey (CJMP) and Professor Ehrenberg himself
(he again proved to be wonderfully patient and helpful with all my questions).

The existing parts of the system to remain on the car:
a. hard hydraulic lines on the body (they were all replaced already with new)
b. master cylinder (it's also been replaced) - although that story isn't over, I feel
c. drums (I have several of both sizes already; the best will be chosen, machined and used)
d. backing plates (no rust, keeping them)

Everything else gets replaced with new stuff. Cylinders, hoses, linings, hardware, all of it.
When I'm done, all things braking will be better or they won't - but I won't leave anything on
the table in regards to restoring the closest thing to factory drum brakes that is possible.

Total cash outlay: $300.00
Not kidding...

I don't suppose anyone would be interested in a thread on FBBO of me doing the work?

 

[33 IMP]

I would! Considering ive got a drum brake 69, and currently fighting a brake problem on my drum brake 62.....
(And ive got over $100 so far, just in two hoses, two wheel cylinders, and some return springs.....)