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Brake Dust Cleaning

I’m a bit of a newbie when it comes to car repair, but I’m slowly building the confidence to tackle slightly larger jobs – right now I’m looking at doing basic brake pad/shoe replacement/maintenance. Just to start out, I want to take the wheels off and do a visual inspection before taking anything seriously apart. On the back drum brakes, I’m expecting to find a ton of brake dust, which is where my question comes in. I know that the brake shoes are lubricated against the backing plate, but if I were to douse the wheels with brake cleaner, would that remove the lubricant as well? If it does remove the lubricant, I’m assuming I’d have to take everything apart just to relubricate – which I don’t really want to do just for that.

You can use a screw driver to pry the shoes away from the backing plate up to about a 1/4". No disassembly required. You can put some grease on the end of a popsicle stick or even a q-tip to apply the grease to the pad on the backing plate.

My auto-shop instructor – this was years ago – he’d simply take a garden hose with a gentle stream of water and wash the brake dust off the works before doing work on the brake system. That’s how I do it. Usually if I’m taking the drums off, I’m intending to replace the shoes, and I’ll need to relube anyway, so after rinsing the stuff off with water, I’ll do it again, but brake cleaner. As mentioned above, if you aren’t replacing the shoes, it is usually fairly simple to poke some brake grease onto the lube spots without removing anything.

In all the drum brake jobs I did at the shop I never used brake lube for the shoes, my cars included. Never noticed a problem.

A garden hose works juts fine…Lubing the backing plate/shoe contact point is not that critical…It may cause more problems than it prevents…

I agree with Caddy and usually don’t lube where the shoe touches the back plate.
After a while the lube mixes with the brake dust, becoming an unholy mess.

As far as I’m concerned, if a repair manual says to lube the contact points, I do it. If you’ve got so much brake dust that it becomes problematic due to it mixing with the lubricant, then you’ve either got shoes that are rubbing inside of the drums, or the shoes themselves are made out of an inferior material that is prone to dusting.

Why don’t you just use some compressed air to blow the dust out? Wear a respirator if you do this so that you don’t inhale the dust, but this way, you don’t have to worry about reapplying the lubricant.

I used compressed air to blow out brake dust on hundreds of brake jobs - but that was years ago before I cared about health effects.
[edit] I would never use it now.

They may have banned asbestos, but that doesn’t mean lining your lungs with all those foreign particles are good for you.

If you’ve got so much brake dust that it becomes problematic due to it mixing with the lubricant, then you’ve either got shoes that are rubbing inside of the drums, or the shoes themselves are made out of an inferior material that is prone to dusting.

Err, brake shoes rubbing against the drums? Isn’t that how they work?

Fact is all shoes/pads wear and cast off the particulates. It doesn’t matter what they’re made of, if they’re worn down the material went somewhere. If they’re not worn down why are you servicing them?

For drum brake inspection if I find they don’t need replacing I just tap the drum on the ground to clear the loose stuff and re-install.

Count me as a never lubed guy. I prefer dry and clean. Never had an issue with brake performance.

DO NOT USE COMPRESSED AIR! Asbestos is still used in some brakes. I, too, thought it had been banned, but it hasn’t. I use brake cleaner with a number of paper towels spread out below to catch all the runoff, then throw out the paper towels.

As for the lube, I never remember seeing any wear on the backing plates. And think about it, the shoe is going to move, what, 1/4" max? And it’s not pressing on the backing plate, it’s just sliding by. But use it if you like.

I use a little moly lith grease, never had a problem with it gunking up. It does get some dust on the surface, but it isn’t a problem.

Re: the grease: it’s like Brylcream (for us old guys)…“a little dab will do ya”.
People often think that globs of lubricants are better than dabs. That ain’t usually true. Especially in an application exposed to dust of any kind.

If anyone had read my advice fully, I stated that if compressed air is used, then a respirator should be worn. As for brake shoes rubbing on the drums, I meant that the shoes were sticking and wearing on the drums even when the brakes are not applied. This could result in excess dust forming.

I had a car once that squeaked when the parking brake was applied because the lube on the backing plate dried out.

I can tell most you guys don/t line in the salt belt. Around here,you use grease on the backing plate if you want the shoe to retract, a new spring kit with every pad replacement and if your car is driven 6000 miles a year or less, you might have to disassemble everything to wire brush and re-lube the parts even though the shoes are good. I have never seen paint on the inside of a backing plate, only rust.
I know two people who own 2006 Hyundai Sonatas and both got only 20,000 miles out of their rear pads. Their dealers are telling them that their rear disc brakes have to be disassembled, cleaned and lubed YEARLY!

When asbestos was a problem on friction material for brake components back in the days, we mechanics starting using Scrubbing Bubbles or DOW bathroom cleaner to remove brake dust. You could spray this on the brake components, and the foaming action of the bathroom cleaner would prevent any dust to become airborne. Then after allowing the bathroom cleaner to soak the brake dust, you wash it down with brake cleaner into a capture container.

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