Front Drum Brake Dilemma

[pschlosser]

the studs are splined and press-fit into the hub.  but I would not reuse any studs, so press them out for disassembly, but replace with new ones on assembly.

photo for reference

[Mopar5]

After a bit of research I can make a summary of what I think Ineed:
1) Two 11" drums Raybestos 1938R (stud hole=.64" should be a minor friction fit for stud)
2) 5 LH studs Dorman 610-133L (have 7 brand new ones in my hand)
3) 5 RH studs Dorman 610-132 (1 5/8" length, 11/16" shoulder, .65" Knurl) (easy to get)

Hole cutter.... can I use a normal .75" metal hole cutter or do I have to purchase the specialty tool?

Well I hope I didn't screw up I bought the Raybestos drums and slid them over the lugs and the hub haven't run them yet now so I hope there is no issues. I have 11 inch front drums so I just put the hub back on the spindle and the drum just centers itself and is free floating. Seems to be OK Now Im second guessing myself.

[RUNCHARGER]

There's no movement? The hub is tight on the center of the drum? That's the way it should be. Bolt a wheel on and spin the assembly and adjust the brakes. You'll figure out right way how close it is to being machined correctly.

[Mopar5]

There's no movement? The hub is tight on the center of the drum? That's the way it should be. Bolt a wheel on and spin the assembly and adjust the brakes. You'll figure out right way how close it is to being machined correctly.

There is not much play but is definitely not a press fit. I will put a tire on later and check it again.

[Mopar5]

So it appears that the drum is centering on the lug shoulders. Not a press fit like original but no noticeable slop. I will put the tire on shortly.

[pschlosser]

So it appears that the drum is centering on the lug shoulders. Not a press fit like original but no noticeable slop. I will put the tire on shortly.

Press fit, or not, the friction holding the brake drum to the hub does NOT provide the majority of stopping force.  Front disc brake rotors FLOAT, and in the rear, the drums float.  By this, I mean, the metal doing the stopping (drum or rotor) relies most on the 5 studs going through it, and securely fastened to the wheel (rim+tire)

As long as there is NO PLAY, or wibbly-waggly movement of the drum to the hub, it will be the 5 studs bolted to the wheel that provide the secure stopping force.
Your "not a press fit, but no noticeable slop" borders perfect, IMO.

[RUNCHARGER]

Ok: I'll tell you a story. I bought a 1970 D100, 4 wheel drum brakes of course. Same architecture as our beloved cars. I had to have the truck safety inspected. I went through this same dilemna, 2 original drums were out of spec. So I bought the last 2 front drums from NAPA. One was perfect, the other one, well the register hole and wheel stud holes were machined 1/4 inch out, so the drum braking surface travelled up and down 1/4 in a rotation. That's why I'm asking. Funny sidenote is the mechanic measered these new drums, recorded on the paperwork and passed the truck. Thank gosh he didn't road test the darn thing.

[Fire_Billy]

I've come to a crossroad and am pondering options.
Virtually completely stock 1970 Plymouth Cuda 383 started vibrating the steering wheel when braking at high speeds. Thought the front drums were out of round. Took them to a shop to round out. Shop said "no can do" as one is below spec and the other will be below spec when rounded. Shop cannot find replacement with an integrated hub not to mention LH studs in one side. I told them to stop as I consider the future path.
So I face some options.
1) Try to find new ones as a complete set. Likely cost a ridiculous price if I can find.
2) Continue to run these which I don't really want to because of vibration.
3) Purchase the new drums without the hub and try to attach the hubs to the new drums. (shop told me they would always be separate and "matched" and not attached)
4) Switch to front disc brakes which I also don't like since the car is OEM with front 11" drum.
There are probably other options but at this point I feel discouraged with the choices I see. Others must have faced this problem.
How do you recommend I resolve this issue???
I would be grateful for any suggestions or guidance.

Finding correct drums with integrated hubs is definitely challenging. Others have had success with quality used parts or sometimes carefully matched separate drums and hubs. Upgrading to discs is an option but not for everyone. Keep us on the know, there's usually a solution with some patience and the right contacts.

[moonshine_mike]

Completed some updates to the 11" front drums today but have not test driven the Cuda.
I cut around the studs with .75" circular bit essentially cutting the drum material.
Only deep enough to get the swage. (a couple do go deeper). Then the hub pressed out with very little pressure leaving the studs unharmed except the small swage section of stud. Then simply slid on some new pre balanced drums. The drum stud opening holes were only a miniscule larger than the remaining studs so there is definitely no press fit here. But she went back together very easily. If the drum does shiver slightly on the hub during test ride which I don't expect, I will have to rethink things and might redo the studs. if I feel a shiver during high speed stopping I can still rebalance the entire assembly also. I'll repeatedly test drive the Cuda in the next couple weeks and provide another update.   

[Chryco Psycho]

I did what Runcharger / Sheldon did & just saved the front drum set up , probably very good given less than 40k miles , then installed 12" front discs & a proportioning valve & disc master cylinder . If I ever sell the car the front drums will be available .
 I am not willing to risk the car because stopping is compromised with 50+ year old drums , it seems crazy to me that the highest HP cars in history up to the last 10 years came with crap brakes , At least the new cars have brakes matching the power finally !

[moonshine_mike]

Took about one month of wait, but finally got to test drive the Cuda with the new modified front brake drums today. Solution worked perfectly... No shake, no drift, no pull, short distance stop capacity great. At this point I'm very happy with the solution taken to reservice front drum brakes that are well beyond normal service life. Cut around studs to depth of drum to release drum from hub/studs. Hub remains with original left and right factory studs essentially unscathed. Add new drums via Rock Auto.  They float very minimally but are still firm. Viola...