New Front And Rear Brakes Drums Rotors Shudder

Imatk

Active Member
Apr 17, 2005
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So I have a fairly bad shudder when I apply my brakes under any kind of actual speed or load (like on a hill going down) and I thought it was just the car needing either front or rear brakes.

So I just replaced the brakes.

Rotors, Drums, Pads, Shoes.

I'm still getting a shudder that's coming from the passenger rear wheel specifically.

The passenger rear also gets a bit hotter than the other rear wheel and much hotter than the front wheels and I can smell brake shoe or some kind of material from the brakes after driving them.

I've tried adjusting them more than once and can't seem to get it to stop.

What am I missing here?

Thanks for any help on this one.. I'm stumped.
 
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You might have play in that axle bearing. Was there any grease or oil on the backing plate ? Can the axle move up and down in the axle tube ?
 
You might have play in that axle bearing. Was there any grease or oil on the backing plate ? Can the axle move up and down in the axle tube ?

I didn't notice any grease... I can try and see if the axle moves though.

Also this doesn't occur until the brakes have warmed up.

When they're cold there is no shudder or noise.
 
Does the rear wheel drag when the brakes have been warmed up and the wheel is off the ground?

The most likely cause of the shudder is that the rear brake drum is out of round. If the rear drum is severely heated and then the parking brake is set, it will tend to deform the drum. This can happen if the self adjuster is improperly assembled or the primary and secondary brake shoes are in the wrong position The diagnosis and cure for problems with the brake drum are the same thing. Remove the drum and have it lightly turned. Any area of the drum that does not have the marks from the cutting tool shows that the drum is out of round.


Drum brake assembly

When you install the brake shoes, remember: short shoe goes towards the front of the car.

Here's two pages out of the factory shop manual...

Click on the drawings to enlarge them to full size.

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Thanks I'll see if it will drag when I get home from work tonight.

I'll also check to make sure the shorter brake is in the front.

So even a new drum would be out of round?
 
Thanks I'll see if it will drag when I get home from work tonight.

I'll also check to make sure the shorter brake is in the front.

So even a new drum would be out of round?
If it gets really hot and you set the emergency brake, it is possible.
 
Ok so I'm at a complete loss here.

I actually replaced the drum and shoes on the passenger side, and it still binds.

The driver's rear wheel turns freely but the passenger (the problem wheel) turns but noticeably binds at one spot.

I checked the axle and it is SLIGHTLY bent, but like 5 one thousandths of an inch so I don't think that enough to cause this issue?

The car has never been wrecked so I didn't THINK the axle had a problem, but with the wheels off and having someone in the car on the gas you can see a very slight wobble.

Also the drum doesn't sit flush on the backing plate at all.

So I'm not sure if it's the drums... like maybe I have to try a different brand?

I've adjusted the rear shoes a bit so they don't grab as much.

So I basically have less brake in the rear, but the shudder is gone.

I still notice it if I get on the brakes on say a steep hill... but that's only when they really heat up.

At this point I'm not sure if I should just leave well enough alone or if there's something I'm missing.

Any advice?
 
I spent Wednesday replacing the rear brake shoes and I can tell you that it you didn't use the picture of the brake assembly I posted, you probably have it incorrectly installed. The springs and shoes are position dependent and without the drawing right in front of me, I would have gotten it wrong. I have been working on cars with drum brakes for 50+ years, and the Mustang drum brakes are different from any that I have ever worked on.

Short story, check the actual assembled brake against the drawing, making careful note of the FORWARD ARROW that points you towards the front of the car.
 
New drums can warp during shipping or being stacked on top of each other in storage.

I'd advise you to swap brake drums from left to right. If the problem follows the drum then you have your problem narrowed down.
 
My two cents say to replace the axel and bearing on the offending side. Wobble means not straight. Axels need to be straight, that may be why the drum does not fit flat on the face of the axel if I read that post correctly.
 
So I've gone through two sets of drums and shoes and replaced the axle... although I didn't replace the wheel bearing.

Now I'm thinking I should have replaced the wheel bearing because it's STILL doing it.

Other than the brake drag, the wheel bearing is silent but do you guys think that could be the culprit?

At this point it's the only thing I haven't changed aside from the wheel cylinder.. but it wasn't leaking so I left it.
 
I don't think the bearing would be a culprit, but they are cheap, so perhaps why not just do it and eliminate it as a source.

I would however change the wgeel cylinder. Another cheap part, and probably more probable cause of drag. At least doing that will allow you to rebuild the drums again to check if everything installed correctly.

And if that doesn't work, convert to rear disk and do this
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Actually when you replace your wheel cylinder, please replace both sides. Replacing just 1 can sometimes lead to uneven stopping, not to mention leaking on the side that you didn't replace. Also bleed system. J richker is right about assembly. Be sure you have all springs on right, shoes are centered. You can't have any thing like a bent axle, or improperly installed shoes/ hardware. Have both drums spun on a brake lathe, and lightly cut to be sure their is 0 run out. Leave shoes a little loose, that's what I do on my emergency brake shoes on my 2000 expedition. Till you get a handle on this, it's better to have a little less rear braking, than to have them drag or lockup on you.


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Wheel cylinders haven't been replaced, but that will be my next step. To do the bearing I gotta pull the damn axle again... or so I think?

The springs and shoes have been triple checked and they are on correctly and centered.
 
Wheel cylinders haven't been replaced, but that will be my next step. To do the bearing I gotta pull the damn axle again... or so I think?

The springs and shoes have been triple checked and they are on correctly and centered.


Yes, axle need to come out again. I'd just do wheel cylinders first.


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The axle should have literally 0 runout. Think about it, if the axle wobbles, so does drum. If your new axle is perfectly straight, I'd hold off replacing bearing unless theirs noise. You can always change it lateras long as it's not badly worn.If in doubt if straight, clamp a dial indicator on it. I don't think you need to go that far. E brake cables can be lubed and saved in most cases. Just make sure adjusters are on loose side. For brake shoes and cables. Your getting close to close enough on your problem. Keep us posted on end result.


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