1960 Cadillac brakes pulling

[Oz Power]

Hi all. I have a persistent problem that my self, my mechanic and the auto shop cant solve after many months.
Basically my caddy pulls to the left when braking slowly at say 10 - 15 mph.  As soon as you apply the brakes at minimum pressure the car starts to pull to the left. If you apply the brakes hard or at great pressure at normal speed it stops firm and straight.  Its obviously something simple but we cant nail it.
We have :
replaced the entire braking system.
Checked for kinks in the new brake lines.
Checked rubber hoses ( all new)
Replaced all springs and wheel cylinders.
Replaced and machined Drums ( Reproduction and second hand from another caddy )
Swapped tires and wheels across the front
Arced the pads using old arching machine
Changed the pads in case of contamination
Checked the pads with chalk markings chalk to ensure contact with drum ( even chalk contact seen on drums)
Replaced all front end suspension including bushes, arms sway bar etc.
Checked idler arms
Done several wheel alignments ( nothing wrong)
replaced all rear wheel drums,discs, pads,wheel cylinders etc

So we have a thorough new systems that stops great under normal braking , but pulls under light braking...

Any advice would be greatly appreciated...

[Glen]

Maybe the problem is in the rear suspension.    Looks like you replaced everything in the front. 

[The Tassie Devil(le)]

Are you running Cross ply tyres, or Radials?

If Radials, have you performed the wheel alignment to Factory Specs for 1960, or altered for Radials?

Radials require different toe-in specifications, for a start.

Bruce.

[Michael Petti]

Did the car run true before the brake job?

[fishnjim]

I'd methodically rebleed the whole system and flush the fluid, first.   Make sure all the air and crud is out.
Most likely not getting even fluid or pad adjustments, but could also be in the steering, too loose.   Bit-o-wobble as they say, ball joint, box, end link, link, suspension arm, etc..   
Speed = momentum, so not as likely to veer when faster.
There quite a bit force when the brake is applied, and if the suspension holds it more on one side, it'll wander.
Some of these "gremlims" you just may have to live with, they die and go away if lucky, if not, they get worse and become obvious.   Unless it's unsafe, how often do you brake at low speed and how severe the pull is, determines if tolerable.
I don't recall if the '60 has self adjusters, or manual.   Too lazy to look it up right now.
Probably one of those things that's lost to the ages.   Some old timey mechanic would fix that in a heart beat, but today you have to figure it out again.   He'd probably take it out and "open it up" and jam on the brakes a few times...aka wear it in.   (guess)
If the lines were replaced, one side maybe plugged or too long.
Perfect is the enemy of good.

[David Greenburg]

‘60 was first year for self-adjusters, and since everything is new they should not be frozen. So you could try making several hard stops in reverse, which should set the adjusters if they’re working properly.

[gkhashem]

Well new means Never Ever Worked.

Last  pull I had like that was a bad hose. While hose looked new it was restricting fluid on the inside. So uneven fluid as you stated in my case.

Does the side that grabs quick get real hot? Sometimes hose will not let fluid return too, so mine got hot since brake did not completely let go unknown to me. I say you got a defective new part somewhere. Did this happen before the brake job?

[Scott Halver]

Hello Joe,
I had a similar situation on my 1960.   A friend told me to take my laser heat gun, drive the car about 1/2 mile and then stop, get out and "shoot" the back of each wheel (backing plate).   About the second stop I had my answer, left rear was significantly warmer than the rest of the brakes-   not smoking hot, just warmer.   That did not solve the problem, but at least I knew which wheel/brake was causing the problem.   Myself and other car guys would have swore that it was the left front causing the problem.   SHalver #24920

[savemy67]

Hello Joe,

A few weeks back, there was a thread here about the brake backing plates.  The backing plates have six "pads" on which the shoes ride as they expand outward toward the drum.  On many older cars, these pads develop sufficient wear to cause the shoes to hang up upon brake application.

A pull to one side upon light brake application at slow speed implies that one wheel's shoes are making contact with the drum before the other wheel's shoes.  You may want to check the condition of the backing plate pads front and rear.

Respectfully submitted,

Christopher Winter

[gkhashem]

Hello Joe,
I had a similar situation on my 1960.   A friend told me to take my laser heat gun, drive the car about 1/2 mile and then stop, get out and "shoot" the back of each wheel (backing plate).   About the second stop I had my answer, left rear was significantly warmer than the rest of the brakes-   not smoking hot, just warmer.   That did not solve the problem, but at least I knew which wheel/brake was causing the problem.   Myself and other car guys would have swore that it was the left front causing the problem.   SHalver #24920

.

Same tell tale sign, hot wheel may tell you which wheel is the culprit. May not tell you the cause but may narrow it down to one wheel. In my case it was smoking.

[Oz Power]

Thanks Michael, the car ran true and straight for many years before I had to have brakes redone.

[Oz Power]

Thanks all, for your comments.
We have redone all the lines , bleed them several times to ensure the fluid is working evenly etc.
I think , the areas we haven't concentrated on is the steering itself. So Ill get that checked out...
Although we have fitted out new pads , wheel cylinders and machined rear drums.. We may need to look at the rear over again thoroughly.  It maybe that its a rear drum / pad sticking.
Ill try all of these suggestions and let the forum know how I go..

It may sort itself out , as it drives more. Its not dangerous , but annoying...

Thanks for your help....

[Michael Petti]

check your emergency brake cable. If tighter on one side than the other it could cause the issue you are talking of. rust or dirt in the mechanism could cause this problem.

[brian faull clc#25881]

I see you have machined the drums, but were they measured as well? I have seen lots of cars with all new brakes, that have drums cut / worn way beyond spec. Also, definitely check your backing plates to make sure you do not have grooves worn in the slide pads. Have you replaced the brake spring kits? Uneven spring pressure could be an issue as well. Also, Did you do the major brake adjustment as outlined in the service manual? This will often alleviate similar problems. I feel after 60 years, they are all due for this, as it was probably not done very often. If you check all those items and still have issues, You may consider a faulty rubber hose or wheel cylinder not working properly as well. Hopefully you can track it down. Good luck on your project. Thanks, Brian.