So been trying to figure out this front brake problem I’ve been having,maybe somebody can shed some light on the problem. End of last season I changed the Brake shoes, springs, cylinders . Brake hoses, adjusters. And had the drums cut at a machine shop. Using good quality parts Raybestos Bonded shoes, bendix cylinders & Hoses.Centric springs and all seemed well, till the front end started shaking when braking at speeds over 40mph. Or coming off the expressway THAT WAS ROUND ONE.....
So the drums were not getting hot, or dragging,it seems I had them adjusted correct , I have one of those tools that measures the drum and shoes,it works very well. I took the drums to the machine shop and had them skinned again and I changed the brake shoes to a Rivited type of brake shoe all went together nicely.I also checked the front end, tie rod ends ,ball joints etc. all is good. Also took the front wheels in to get re-balanced .bought new tires last year . STILL having the same problem ..... anybody got any ideas ?
Ray, Did you seat or bed the brake shoes as noted in section 6. Break-In of New Linings on page 6-7 of your 1964 Shop Manual? I always "seat" all new brake shoes or pads once installed. I scanned thru all the replies and didn't see where you stated this was done. If not, might be worth giving it a try. After, seating them might try readjusting them and seating one more time. I know on my big ole Escalade it sometime take 10 or so moderate rapid stops to get thing smooth out. Different technology on the shoes, but same principal. I remember doing this with my 64 CDV about 15 years ago, and never had any issue with the aftermarket shoes. Of course parts change in 15 years!
Due to the --brake adjusting slot --being at the front of the drums on our year Cadillacs --which is not the norm for most cars
I do the following:
I put the tire on the hub with two lug nuts --off the ground
You need to get the brakes adjusted with the spoon so that a strong pull on the tire causes it to rotate --one full turn and stop were the tire started
The tire has to be put on and off the drum until the adjustment is correct
That was how i was taught to adjust the brakes by --Arthur Fonzarelli ( or my very good friend Ben Mattana super race mechanic - one in the same )
You will hear and --feel just how tight to the drum the shoes are that way
Never saw the tool you are using so not sure that is getting the job done myself
Might just compare the results to see if that spacing could be the solution to this nightmare of a brake issue
Properly seating the brake shoes to the drums is necessary and normal proceedure as Jason has explaineed in his post
Run the car up to 50 MPH hitting the brakes fairly hard to a stop a half dozen times allow the brakes to cool between the stops
I see you have the self adjusters still on your brakes so you can back the car up at 5-10 MPH and hit the brakes to have them self adjust as they wear in some
You do need to know the brakes are clean and in good working order For the self adjusters to work as they should
If not working correctly you may find a wheel getting a bit to tight and the drum will get hot and possibly cause the steering to pull in one direction or another
If that happens inspect the self adjuster and readjust the brake adjustment as explained above
I am running out of ideas but wanting to know the basic adjustment is correct at this point
I realize at this point in time i kind of do this brake stuff by feel ( spin the drum till it feels right )
I do back off the nut on the hub a few notches to where the carter pin will fit trough the hub nut to lock it in place -which is closer to the 1/4 turn ( not two turns as i stated )
A good correction my friend
The weather here in Chicago has been crap lately, waiting for it to clear up. Plan on taking it out for a ride and see if I can get theses brakes to set in . I will find an open lot and do some reverse shots, Then do the forward process and see how that works out , I’ll get a little more aggressive with it. Lol
Thanks for all your help guy’s, I’ll let you know the outcome in a day or two . Weather permitting...
In preparing to drive the nearly 700 miles one way to the 2019 Grand Nation in Louisville, I thought it might be the time to tackle the brake issue again.The previous 2 sets of shoes I tried were Raybustos; one set riveted and the other bonded. As I stated earlier, they both cause severe shaking when braking over 40 mph. So bad in fact I ended up putting the old brake shoes back in and have been driving with the old shoes for the last 2 years. At the time, when I inspected the Raybustos shoes, they were cracked, flaking and glazed. I don't know if I got a bad set but clearly they did not hold up to the heat of stopping these heavy cars.
This week I picked up a new set of brake shoes from NAPA; bonded shoes #TS-127. During the install I did all the correct procedures following the manual even torquing down the wheel bearings to 30 ft-lbs; baking off 1/4 turn. I took the car out for a test drive and to my disappointment I had the shaking again but this time noticeably less then the last time I changed the shoes. After rereading this post I realize the one thing I didn't do, as Jason stated, on page 6-7, BREAK-IN OF NEW LININGS! After many "moderate" (really more then moderate) stops above 40 mph, the shaking became less pronounced. Next I took the drums off, cleaned shoes as the manual states removing all the lining dust, sanding the shoes, re-torqued the bearings, and adjusted the brakes. I took the car out again for some more "moderate" braking. Now the shaking was almost non existent! I still have a very slight vibration when braking over 60 mph but I'm hoping it will go away on my way to the Grand National. I hope my story will help someone else.
Bob, "Bedding" the brakes is a must. I usually do about 10 medium to hard stops after I install any new shoes or pads. I'll usually run up to about 60 mph and bring to a complete stop, not slamming on the brakes, but giving the pedal a firm push until stopped, then repeating. Think of this like breaking in an engine where the rings "seat" against the piston walls. I am glad breaking in the shoes and other steps reduced the vibration. Looks like you are on the road to smooth sailing ... or smooth braking in your case!
I think with the disc pads it trues the flatness of the surfaces with each other, but with the shoes it aligns the curvature of shoes to drum. I would guess any bit of out of alignment, curvature-wise, might cause a bit of vibration at different speeds or under different braking conditions.
Sooo, last couple of days I took the car out for a ride, went to a nice open lot and got a little more aggressive on the braking. Forward 3-4 times and reverse 3-4 times 35-40 mph. It seemed that it brought my pedal to a more firm braking, then I took it on the xpressway got it up to 70mph for a bit ,got off at the exit and started braking at 50 mph and it was a lot better than it has been, I pulled over by a shopping mall on the way home and got out to feel the wheel hubs to see if there were getting hot ,noticed the right rear was really hot all the other wheels weren’t really too hot at all. So when I got home I took off the right rear wheel and adjusted the brake . Took the car out for a 1 1/2 hour cruise , back on the expressway and when I exited very minimal shaking. So I’m thinking either I wasn’t aggressive enough on the proper way in setting the brakes, Or the first set of brake shoes were defective, I went from bonded type to riveted type....who knows . All I do know is I’m braking straight and not shaking. Thanks for all the advice guys.
Glad the car is back to Smoooooooth Riding
I know the relief you must be feeling ( i remember my own )
New brakes seem to alway be a softer peddle until a little time is put on them
Enjoy your road trip to the CLC
The brakes working will make that a better experience --LOL
Jason did a good job of pin pointing your problem
I enjoyed your thorough approach to the brake work you did to get it right
Rabestos brake shoes are cut to the drums when you purchase them ( no one else does that )
That being known not sure why the seating of the shoes was such an issue
Whats more important it solved the chetter issue and back to normal