A Body Disc Brake Swap 101

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7071DartGTReg

Deceased - RIP Bruce
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OK Then....
I am getting started on my Disc Brake Upgrade/Swap on my 1970 Dart GT. Since it seems that nobody has posted a step by step with PICTURES I am now going to do so. This is for 67-72 SBP cars to the 73 - up LBP Brake setup. It may work on older A's but I am only saying what I know it fits.

This is the Old School swap using used parts... NOT a "Kit".
As for other parts and pieces that can be used to do the swap; There are many other threads to help you with this. So if you don't mind, Please don't ask me about all the other interchanges in this thread. Thanks!

Starting out.
You will need to find donor parts from a 1973 - up A body with Disc Brakes to get the parts from.

You will need the following:
Upper Control Arms (Grab the Cam Bolts for "Just in case" too).
Spindles with ALL attached parts (Spindle, Caliper, Caliper Mount, and Rotor/Hub). Don't forget the Lug Nuts as they are bigger than Small Bolt Pattern Lug Nuts. Proportioning/Meter Valve. I am not recomending you get the Brake Soft Lines because I would use new ones. But you may want to get them for reference purposes. You will also need Big Bolt Pattern Rims.

Also, This would be the time to rebuild your Front End too! Hint Hint.

Hose down the Upper Ball Joint Cam Nuts and the Brake Lines connectors with WD-40 or ?? of your choice at least the night before you start this project!

That's it!

Now, just a note on MY cars swap; I only bought new Upper Control Arm Bushings, Upper and Lower Ball Joints since her Front End has less than 10,000 miles on it from the last rebuild.

OK then.... Off to start this! I will post pics later today as we get 'er done.

Thanks for looking!
Bruce B.
 
Hey Bruce, great idea, now I am going to be doing a similar swap, but going to use a disc brake sbp from 68 cuda to my 69 cuda. I shoulda asked the guy about upper control arms. I will have to get those. As well I may need the proportioning valve. I planned on using a master cyl and booster from another drum brake car, but I think I may need a different master cyl.
 
Hey Bruce, great idea, now I am going to be doing a similar swap, but going to use a disc brake sbp from 68 cuda to my 69 cuda. I shoulda asked the guy about upper control arms. I will have to get those. As well I may need the proportioning valve. I planned on using a master cyl and booster from another drum brake car, but I think I may need a different master cyl.[/QUOTE


You won't need to change your upper control arms. That's only necessary when swapping on the 73 & later disc brakes. The sbp stuff uses the same upper ball joint. You will need a different lower ball joint though.
 
I believe the OP is discussing a BBP conversion.

You can also use FMJ spindles and they work FINE!

65-72 cars need the 73-76 upper control arms, sleeve modded on current arms (stock car products) or Dr Diff's ball joint sleeves to install the later style big ball joint spindle.
 
I think it's a great idea. We all could use a step by step instructional along with picts. People could post tips and tricks that make it easier for all of us.

My Dart is up on 4 jack stands right now. I bought my brakes as "a kit" from Master Power, but it uses all stock BBP A body parts. I also have a PST front end rebuild kit that I am going to be installing. I planned on taking pictures as I went and I have a factory service manual on CD that I planned on using.

This thread couldn't have come at a better time. I will begin stripping the front end down next weekend.
 
OK... First of all: SAFETY IS #1 around me and my "shop"!
Put your car on Jack Stands at the front of the Frame Rails.....
PLEASE, PLEASE, PLEASE make sure your Rear Tires are blocked!

Before - Front View
2010-02-19 70GT Brake swap (0)s.JPG

Before - Rear View
2010-02-19 70GT Brake swap (1)s.JPG

Step #1 - Remove Outer Tie Rod End
2010-02-19 70GT Brake swap (2)s.JPG

Step #2 - Remove Brake Line
2010-02-19 70GT Brake swap (3)s.JPG

Step #3 - Remove Rear Upper Control Arm Cam Bolt
2010-02-19 70GT Brake swap (4)s.JPG

Step #3 - Remove Front Upper Control Arm Cam Bolt
2010-02-19 70GT Brake swap (5)s.JPG

Step #4 - Use your Floor Jack to support the Lower Control Arm to ease in pulling the Upper Control Arm out from its Mounts.
2010-02-19 70GT Brake swap (6)s.JPG

Step #5 - Remove the Lower Ball Joint CAREFUL! The entire assembley will hit the floor when you pop it loose.
2010-02-19 70GT Brake swap (7)s.JPG

Here is the view of the Drivers Side completly removed and ready for whatever detailing you want to do.
2010-02-19 70GT Brake swap (8)s.JPG

And here is the view of the Passengers Side completly removed and ready for whatever detailing you want to do.
2010-02-19 70GT Brake swap (9)s.JPG

OK.... That wasn't so bad was it? Do yourself a favor and buy some "Special Tools" before you start on this project: A Flare/Line Wrench Set and A Pickle Fork. This will save you from destroying your Brake Lines and ease the removal of the Tie Rod Ends and The Lower Ball Joints.

If this tutorial seems overly simple PLEASE don't get me wrong! I have done 10 (soon to be 11) of these upgrades. So please be careful and if you have ANY questions ask someone that has experience with this level of mechanics before you screw something and most importantly yourself up!

This is the end of the removal section. I may be a week or so before I am gonna have time to detail and install my Disk Brakes. Please be patient with me!! I will post that segment as soon as I get 'er done!

Don't forget to take the poll at the top of this thread please.

Later,
Bruce B.

2010-02-19 70GT Brake swap (0)s.JPG


2010-02-19 70GT Brake swap (1)s.JPG


2010-02-19 70GT Brake swap (2)s.JPG


2010-02-19 70GT Brake swap (3)s.JPG


2010-02-19 70GT Brake swap (4)s.JPG


2010-02-19 70GT Brake swap (5)s.JPG


2010-02-19 70GT Brake swap (6)s.JPG


2010-02-19 70GT Brake swap (7)s.JPG


2010-02-19 70GT Brake swap (8)s.JPG


2010-02-19 70GT Brake swap (9)s.JPG
 
Thanks for starting this thread Bruce. I have a couple of questions/suggestions.

Shouldn't your first step after putting the car on jack stands be to back off the adjusters on the torsion bars? This will take all of the pressure off of them, and you don't have to worry about using the jack under your lower control arm.

Also, could you make the pictures a little bigger? Some of us are working off of laptops and can't see the detail in the pictures.

Here is a link that also has some good information and LOTS of pictures!!!

Mopar Action Tech Archive

Keep up the good work, I'll be following along!!
 
Bruce,
While Im not going to need this info as Im installing an Alterkation piece, I cant thank you enough for taking the time to document the conversion process.
This type of information is why I love this site and think so highly of the people that frequent it.
Andrew
 
One more thing to take from the doner car is the master cylinder.

Also, I don't recomend that the master cylinder, or calipers be used but they are good to use as cores when getting rebuilt parts.

Unless the rotors are very good I would recomend new ones, they are relatively cheap. I got Canadian made rotors for about $45 each.

Another item that should be new are the wheel bearings. They are about $5 each and $3 for the dust seal.

One more item; if you happen to have new lower ball joints on the car already they can be reused. You will need to drill out the mounting holes to accept the larger spindle mounting bolts of the disk brake setup.

DiskBrake.jpg
 
If the torsion bars aren't released first, that knucle and upper arm assembly will come out for sure. It wont be so easy going back in.
Try your diagonal cutting pliers to pull cotter pins. Lever their jaw against the nut in a can opener like motion ( for lack of a better term ).
I rarely use the tapered nozzles that come with products like silicone. Most of them are closed end. Since the flexable brake fluid line will be replaced, cut it and plug it with the tappered nozzle thingy.
 
OK,
I will try to answer the many questions.......
The reason for the Floor Jack under the LCA is to LIFT it to ease removal of the UCA only.
You can then lower and remove the Floor Jack.

Sorry about the pics.... This was as large as the site would allow me to post.

And as for the Master Cylinder.... Individual Preference as per the Auto Parts stores - the Rebuilders only supply a generic "fits all" these days anyway.... Believe me I go through that fight every time I need one. The only Master Cylinder they had for my GT that matched the original HD 10 inch Drum brake one was the Disc one anyway.

And speaking of auto parts stores = Once you do this swap when buying Brake or Suspension parts: refer to your car as the car you got your swap parts offa!
Or they will NEVER figure it out! Example; I need parts for a 1973 Plymouth Duster with a 426 Hemi and Disc Brakes please. Even though your car is/was a 1969 Dodge Dart Special with original Slant 6 and Drum Brakes.

As for the other questions you all seem to have answered them yourselves!

AND last but not least!
Thank all of you for taking the time to read this latest meanderings of a bored old guy! If I have nothing else to share with others it is my 30 or so years of actual experience working on Mopars as a certified card carrying shade tree mechanic! TY TY TY

Later,
Bruce B.
 
I am doing the '73-'76 brake swap onto my '65 Barracuda. I have purchased anything new that I can. The donor that I got my stuff from was a '72 Dart that someone else had started putting the '73-'76 setup on. Nice thing was that everything was hand tightened & came off in no time, bad thing was it was a /6 4 wheel drum car so I did not get a proportioning valve. Any suggestions on finding the correct proportioning valve, new or used? What years will work, maybe F,M,Js also? Parts cars & junkyards are almost non-existent around the Charlotte area. I already have an inline adjuster for the rear drums & a dual res. master to put on. Thanks for posting good detailed steps on this conversion; I will be following it regularly as I get mine started. Getting all the hard parts ready for powder coat so far.
 
Hi Bruce,great thread!I could have used this when I did mine,it was a easy job.I did the swap from a 73 Swinger to my 66 Dart.I got most of my new parts from CarQuest.I also let all the old brake fluid drain out,before replacing the M.C.(I also used the original M.C rod)Great advise,keep up the great work/thread.

P.S Always good to take in for a frontend alighnment after replacing the upper control arm.

trim 028.jpg


trim 029.jpg
 
Once again.... Rained out!!
I finally the UCA Bushings pressed in myself (made up the ole 6 X 1/2 inch Bolt, 3 Washers, Nut, and Socket "Special" tool), Now just waiting for a freakin' break on the rain. I know we need it but still....
My next residence WILL have a garage of some kind.

So keep checking back here it looks like after Wednsday for the Install segment, weather permitting.

Later,
Bruce B.

PS: I notice that 2 members felt that this thread did NOT help them?
Care to share with us why? Please do! Later.
 
Reagarding the ever popular big bolt pattern swap. I understand that the upper control arms must be changed out. How come no one has tried reaming out the original control arms to fit the big ball joint? Is there not enough material?
 
Hey needsaresto.... Short answer: I don't know!
I guess there has always been the '73 up UCA to scrounge so never been tried? I know it is beyond my expertise/shop tools to try myself and be confident of my work.

Good question! Anybody got the answer? Let us know!

As for finishing my conversion....Rain all week again and now I have to head out of town for a week or so. Sorry everybody but I WILL get back to it soon.

Later,
Bruce B.
 
Great thread. This swap works on the early A's as well, just use the early center link, pitman arm, idler arm and inner tie rod ends and then the same 73 up parts used in this thread.

I know some had said you can use your stock outer tie rod ends but that is not the case on the earlier A's they need to match the lower ball joint/steer arm.

I am doing the '73-'76 brake swap onto my '65 Barracuda. I have purchased anything new that I can. The donor that I got my stuff from was a '72 Dart that someone else had started putting the '73-'76 setup on. Nice thing was that everything was hand tightened & came off in no time, bad thing was it was a /6 4 wheel drum car so I did not get a proportioning valve. Any suggestions on finding the correct proportioning valve, new or used? What years will work, maybe F,M,Js also? Parts cars & junkyards are almost non-existent around the Charlotte area. I already have an inline adjuster for the rear drums & a dual res. master to put on. Thanks for posting good detailed steps on this conversion; I will be following it regularly as I get mine started. Getting all the hard parts ready for powder coat so far.

Do you mean an adjustable proportioning valve? If so? That is all you need, it just cuts down the braking to the rear, no need for any other proportioning valve. I have mine mounted below the seat where the knob sticks up above the floor so it is easy to adjust.

Reagarding the ever popular big bolt pattern swap. I understand that the upper control arms must be changed out. How come no one has tried reaming out the original control arms to fit the big ball joint? Is there not enough material?

Because it is just a piece of stamped steal, you would need to have the conversion which you are still running a small ball joint or do what they did back in the late 60's and weld the ball joint section from a B-Body control arm onto the A-Body control arm. It's easier and safer to just get a set of 73 up control arms.

I converted my 70 340 duster drum brakes to the 74 big brake set up. I also bought a new mastercylinder/power brake booster kit. I had no problem doing the swap but, now, no matter what i do, i can't get any pedal. I can bleed and bleed but, i still have to push the pedal to the floor to even consider stopping. I am not sure if i have the right proportioning valve or not. does anyone have a picture of the 74 disc brake proportioning valve? i have like 4 different types. I can't think of anything else it could be unless i have the brake lines hooked up to the wrong sides of the proportioning valve. can you get a diagram of how to do it right?

What kit is it? What size bore does the master cylinder have? What push rod are you using?
 
I converted my 70 340 duster drum brakes to the 74 big brake set up. I also bought a new mastercylinder/power brake booster kit. I had no problem doing the swap but, now, no matter what i do, i can't get any pedal. I can bleed and bleed but, i still have to push the pedal to the floor to even consider stopping. I am not sure if i have the right proportioning valve or not. does anyone have a picture of the 74 disc brake proportioning valve? i have like 4 different types. I can't think of anything else it could be unless i have the brake lines hooked up to the wrong sides of the proportioning valve. can you get a diagram of how to do it right?

Did you bench - bleed the master cylinder, prior to installation?

Also, sounds like you have air somewhere in the system. Did you use new brake hoses, and as previously mentioned - check to see what master cylinder application you have, i.e. the bore size.

You probably already know this, but all factory built 1970 Duster 340s came from the factory with the Kelsey-Hayes disc brakes as standard equipment.
So what you are dealing with - is a car that either was a /6 or 318 car, or someone lifted the original discs. The VIN for all 1970 factory Duster 340s would start: VS29H0* where H denotes the factory 340 build, and zero(0) is the model year.
 
WAAAAY down here in posts but I hope you are reading this BEFORE you start!!!

IF your Upper A Arm Concentric Bolts are fighting back.....
Read this thread 1st: http://www.forabodiesonly.com/mopar/showthread.php?t=85205

Once again..... I am sorry northern people!
This never crossed my southern mind.

Later,
Bruce B.

PS: The reassembly is now scheduled for Saturday 4/10/2010 weather permitting!!
 
Well....
Everything went fairley good....Except:
The Upper Ball Joint on the Drivers side fought back bad!
What you DON'T see is the 7 foot Steel Pipe on the end of the 3/4 Drive Breaker Bar!
2010-04-10 70 Dart GT Disc (8) (Medium).JPG

My friend George (now FABO Member 318dart) stopped by to wrench!! THANK-YOU George!! :supz:
Passenger Side re-assembly.....
2010-04-10 70 Dart GT Disc (0) (Medium).JPG

Spindle......
2010-04-10 70 Dart GT Disc (1) (Medium).JPG

Removing old Upper Ball Joint......
2010-04-10 70 Dart GT Disc (2) (Medium).JPG

Out with the old....
2010-04-10 70 Dart GT Disc (3) (Medium).JPG

Passenger side pretty much done......
NOTE: The Lower Ball Joint Bolts are on BACKWARDS!!! We noticed and corrected this of course! LOL
2010-04-10 70 Dart GT Disc (4) (Medium).JPG

Passenger side waiting on Caliper, Rotor, and Pads.....
2010-04-10 70 Dart GT Disc (5) (Medium).JPG

Now the Drivers side.... (See 1st pic for Upper Ball Joint removal....UGH)......
2010-04-10 70 Dart GT Disc (7) (Medium).JPG

Passenger Side..... DONE!
2010-04-10 70 Dart GT Disc (10) (Medium).JPG

Drivers Side..... DONE!
2010-04-10 70 Dart GT Disc (11) (Medium).jpg

See http://www.forabodiesonly.com/mopar/showthread.php?t=43550
For the pics of the Magnum 500's going on.

This is how it is done.....
Nothing to it!
AND: The Disc Setup clears the Sway Bar with the Sway Bar Mounts I Made.
(see: http://www.forabodiesonly.com/mopar/showthread.php?t=43550&page=2
Post # Twenty-Eight)

Later,
Bruce B.

2010-04-10 70 Dart GT Disc (8) (Medium).JPG


2010-04-10 70 Dart GT Disc (0) (Medium).JPG


2010-04-10 70 Dart GT Disc (1) (Medium).JPG


2010-04-10 70 Dart GT Disc (2) (Medium).JPG


2010-04-10 70 Dart GT Disc (3) (Medium).JPG


2010-04-10 70 Dart GT Disc (4) (Medium).JPG


2010-04-10 70 Dart GT Disc (5) (Medium).JPG


2010-04-10 70 Dart GT Disc (7) (Medium).JPG


2010-04-10 70 Dart GT Disc (10) (Medium).JPG


2010-04-10 70 Dart GT Disc (11) (Medium).jpg
 
Well...
It seems that 4 people felt this thread did NOT help them!
Could I trouble you to tell me why?
I would love to know as I want this thread to help all.

Later,
Bruce B.
 
Well....
Everything went fairley good....Except:
The Upper Ball Joint on the Drivers side fought back bad!
What you DON'T see is the 7 foot Steel Pipe on the end of the 3/4 Drive Breaker Bar!

Nice thread, Bruce. I, too, am in the process of doing the BBP conversion. LMAO, I have both a 3 and a 4 foot cheater bar that I have only used for the purpose of removing the UBJ.

All of the 73 > A-bodies use the larger upper ball joint. (Truth be told there are 3 different ball joint sizes, but the third only shows up on trucks and some early Imperials.)

Attached a photos of tools that are in some cases necessary and others nice to have. For instance the smaller ball joint socket is not needed if you drop the upper control arm and spindle as a complete unit. It's heavy, so watch out.

From left to right:

Torsion bar removal tool, tie rod separator, ball joint separator (aka pickle fork), large upper ball joint socket, small upper ball joint socket.

DSCN2197s.JPG


DSCN2198s.JPG
 
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