brake drums: machine when replacing shoes or not?

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dlb
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brake drums: machine when replacing shoes or not?

Post by dlb »

going to be doing the brakes on my buddy's all trac soon and last time we inspected, the shoes were due to be replaced. the drums were fine so i'm wondering how important it is to have them turned when just replacing the shoes. drum brakes do not seem anywhere near as high precision as disc brakes so i'm not sure if it's really necessary, but then again there's a shop just down the road from me that does it so i was thinking i would do it anyway just to be thorough. what are members thoughts on the topic?
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Petros
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Re: brake drums: machine when replacing shoes or not?

Post by Petros »

the drums will not tolerate resurfacing too often, they get thinner and more prone to warping. They have to be replaced after only one or at most two turnings. Although they do not cost much (almost all replacement drums now come from china), if they are not warped and the face is not scored or damaged, I would just reuse them as-is.

There are those in brake shops that tell you all kinds of silly folk lore on why they have to be turned. If they are in good shape, and there are no issues during the test drive, you are perfectly fine to use as-is. It is just like re-using any other car part, if it meets requirements it can be reused as-is.
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keith
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Re: brake drums: machine when replacing shoes or not?

Post by keith »

I always scuff the contact surface with some sandpaper, just a light scuffing.
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marlinh
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Re: brake drums: machine when replacing shoes or not?

Post by marlinh »

I agree with everyone else, the only other thing I do is remove the rust ridge on the edge of the drum to make removal easier after the shoes are adjusted up.
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dlb
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Re: brake drums: machine when replacing shoes or not?

Post by dlb »

marlinh wrote:I agree with everyone else, the only other thing I do is remove the rust ridge on the edge of the drum to make removal easier after the shoes are adjusted up.
that's a great idea, never thought of that. i will add that to my repertoire.
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