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Knocking Sound as Car Rocks Back and Forth, Motor Mount Maybe, IDK?

Thanks for the help! What is the black piece called with the red x on it called then? I thought this black piece was the dust shield?
See the red x


I believe the drum sits in the highlighted space, between the black part with the red x, and the silver part with the blue x on it. So on my car the silver part with the blue x on it is rusted badly. And I believe as the drum rotates, it’s grinding up against the sheets of rust.

The red x part is the brake backing plate.

It appears that that outer rim “dust shield” is not a separate piece but is part of the backing plate.

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Can you help me find the dust shield online (blue x) at a sore? The only thing I can find is the the backing plate (red x) which rockauto seems to also call the dust shield. I can’t seem to find the dust shield for sale anywhere (blue x).

I have a 2005 Toyota Camry

Rockauto and other auto parts retailers that I’ve checked don’t seem to carry the drum brake backing plate, only the disc brake plates/shields. I haven’t done an exhaustive search, but there doesn’t seem to be an aftermarket drum backing plate available. You’ll have to go to a Toyota dealer or online parts retailer. As mentioned above, the rear drum brakes only have the backing plate with no separate shield as far as I can find. The red and blue x’s are on the same part, if I’m not mistaken.

Ah thanks. So the part on Rock Auto that is titled “Brake Backing Plate” for the rear, for a 05 Camry is not the part with the red x /blue x on it? Sorry if this is a silly question. I can’t tell. I thought that the part on rock auto was the part with the red x. But like you said maybe the blue x and the red x are all the same part.

So what is the part on rock auto that is called brake backing plate for if it’s not the red x/blue x part?

The Rockauto part you show above is for a car with rear disc brakes.

Maybe a visit to a real brake shop and ask if they can get the part . They might even offer a solution to this problem.

You should not be looking to replace any of those components to be honest… In your picture they look absolutely normal. What is it you hope to gain by replacing the backing plate?

If your drums are warped they will cause the shoes to make noise as the drum is no longer concentric internally and it will be tweaking the shoes and springs and everything inside the drum…which will make noise. The shoes are meant to rub just slightly on the drum when they are adjusted properly…if the drum is no longer perfectly circular inside…it will move the brake components and make a creaking/knocking sort of sound.

If I were you I would leave the backing plate well enough alone…and focus on maybe some new shoes and new drums. In the process of new shoes you will also clean up the dirt n dust back there as well.

With new drums and new shoes… I bet your sound goes away. In fact I have 20 bucks sez it does. :wink:

I’ll see if sometime tomorrow i can get a video of it. Sorry, the one in the picture is just some from youtube and not my car. On my car, this thing is rusted badly. I think sheets of metal are rusting off, sticking into the gap the drum sits in. I’ll see if i can get a video of it. It’s so strange that I can’t find a replacement part. Mine is a bit rusty, so I figured I would try and replace it see if it helps. I got new drums and shoes.

These backing plates are available from a Toyota dealer or online Toyota parts sellers, such as here. This one in the link may not be the exact one for your car, as the vehicle production date, and perhaps certain options, must be known to choose the right one.

Oh I see… misleading me with a photo eh? People have done worse to me over time…

Sorry I did not know that was not the genuine article… I thought you were “imagining” rust in places it doesnt exist.

OK… yeah…if your back plates are so rusty they are flexible…then sure it could cause all sorts of mayhem.

Backing plates/shields held on by hub/bearing assy. That can be a big job if hub rusted into place. I have that t shirt. Get all the rust scale out from between and bend the thing back into shape so it doesn’t rub. If no holes, call it a day…


So here’s the video of MY car. I hear the grind/winding/knocking sound as the tire turns. It’s really audible with the tire off. The wheel bearing hub assembly seems to be ok, besides being rusted. With the drum off, and the tire off, spinning the wheel hub makes no winding/grinding/knocking sound. There’s nothing loose inside, but it sounds like it. The slot where the drum sits is really rusty. I think it may be the drum spinning around the deformed and rusted backing plate/dust shield? Let me know what you think

I had to get new tires because of a flat, I also got new drums, and break shoes/springs.

I noticed a hole is completely rotted through it at 6 o clock position, I think it’s time to replace it if a hole is form due to rust? I circled it in blue.

The rust is of no significance, forget about the noise. Focus on your electrical modifications.

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