Disc brake pad slap in the rust belt - can't be done

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Mar 21, 2004
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I say (somewhat loosely) that in the rust belt its darn near impossible to to a pad slap. Basically if you do the pad slap at 3 years, by that time you probably have one of more pads not pressing on the rotor properly because the pad's ears are rusted, caliper pin is rusted or caliper piston is rusted due to corrosion getting past the seal. So the rotor is mostly likely screwed up and cannot be reused.

One of the proclaimed benefits of a pad slap is that you don't remove the caliper bracket, just pull the caliper, slap in the pads, compress the piston and replace the caliper.

However if you don't do the proper cleaning & lube of the caliper pins, caliper bracket where the SS clips go then you are wasting your time on new pads.

In addition if you don't remove the caliper bracket, then the rotor cannot be removed. The rotor needs to come off, lube the hub and replace the rotor (even if reusing the rotor). Or just that much harder when you do need to replace the rotor.
 
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I agree, it's better to do a bit more and get everything working properly. Brakes are an important maintenance item. Plus the rotor and other parts will be easier to remove later on.
 
Around here Mavis Tires does brakes for $89/axle. It use to be $69 a year or two ago. I assume that is a pad slap with a hard pressure upsell of replacing the rotor and maybe the caliper. Never watched but I assume there is not a lot of cleaning and lube going on for that price.
 
Yep, if I'm doing a brake job up here, I'm also getting new rotors. Had a bad experience with a pad slap once where flecks of rotor rust broke off the top of the cooling fins and made a heck of a noise. I agree that the rotor is an easy target of opportunity (after a few hammer love taps anyway) once the caliper bracket comes off for proper cleaning/lubrication. The pedal always feels better with the meat of new rotors as well.
 
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That's why I advocate taking the brakes apart every year. Twice a year may be overkill but then one knows it will all come apart. Bust it all apart, clean off rust, relube, reinstall. If pads are starting to look thin, order up a set and put on the shelf, and install six months later. It's easier to to clean up if you remove the caliper bracket, and then one should remove the rotor at least once, early in life, so as to get some anti-sieze under it.

Usually my rotors are pretty chewed up looking so they get replaced too, although sometimes I wonder if that's just not being overly conservative.
 
That's why I advocate taking the brakes apart every year. Twice a year may be overkill but then one knows it will all come apart. Bust it all apart, clean off rust, relube, reinstall. If pads are starting to look thin, order up a set and put on the shelf, and install six months later. It's easier to to clean up if you remove the caliper bracket, and then one should remove the rotor at least once, early in life, so as to get some anti-sieze under it.

Usually my rotors are pretty chewed up looking so they get replaced too, although sometimes I wonder if that's just not being overly conservative.

Cleaning all the brake parts is not a 5 minute process. I fill up the holes where the caliper pins go with a solvent such as brake cleaner and let it soak a bit. The area of the caliper bracket under the SS clips gets filed and wire brushed then I paint on a paste lube. (South Main Auto uses a sand blaster on the areas under the SS clips).
 
I've given up on just blindly slapping pads on. They all get a visual check of the pins, boots and if the piston is free to move. I also grind some of the pad ears off (just a bit more than the lacquer and burrs really) if i find they new pads are already on the tight side of fitting. if I don't, within a year those pads are stuck tight
 
Cleaning all the brake parts is not a 5 minute process. I fill up the holes where the caliper pins go with a solvent such as brake cleaner and let it soak a bit. The area of the caliper bracket under the SS clips gets filed and wire brushed then I paint on a paste lube. (South Main Auto uses a sand blaster on the areas under the SS clips).

I used to do that, but I found the rust just comes back with a vengeance. Now I take some off the pad ears as the calipers don't tend to rust any further. I just remove the flakes and dust.
 
What is causing the uneven pads wear?
My best guess is pad slaps with no cleaning and lubricating of all the sliding areas.
The caliper and or pad is not able to move freely causing one pad to do the bulk of the work.

Periodic inspections would help.
 
Cleaning all the brake parts is not a 5 minute process. I fill up the holes where the caliper pins go with a solvent such as brake cleaner and let it soak a bit. The area of the caliper bracket under the SS clips gets filed and wire brushed then I paint on a paste lube. (South Main Auto uses a sand blaster on the areas under the SS clips).
No, but it's not an hour either. It will be if I let it go 2+ years though! Six months and it all slides apart. A year and stuff is dry but it'll come apart. 2 and out come the hammers...

It's a good time to pull some brake fluid too. Never have to worry about a "full" flush if you just pull some every six-12 months.
 
Around here Mavis Tires does brakes for $89/axle. It use to be $69 a year or two ago. I assume that is a pad slap with a hard pressure upsell of replacing the rotor and maybe the caliper. Never watched but I assume there is not a lot of cleaning and lube going on for that price.

By "not a lot," that price indicates NONE. If the rotor gets brake cleaner, I'd be surprised.
 
Even when I've done a pad slap, I clean and lube that caliper slide pins.
That's how I do a pad slap. The slide pins have to come out to remove the pads and compress the caliper, so cleaning and re-greasing them I a$$umed was part of the job. Cleaning and lubing where pad ears reside is also part of the job.
 
Pad slaps are a waste of time anyway.
I've done it on my Mercedes, the rotors are usually thick enough. On a cheaper car, maybe not, just have to measure the rotor. Most people advise doing the pad slap once, then new rotors on the next brake job, at least on MB.
 
I say (somewhat loosely) that in the rust belt its darn near impossible to to a pad slap. Basically if you do the pad slap at 3 years, by that time you probably have one of more pads not pressing on the rotor properly because the pad's ears are rusted, caliper pin is rusted or caliper piston is rusted due to corrosion getting past the seal. So the rotor is mostly likely screwed up and cannot be reused.

One of the proclaimed benefits of a pad slap is that you don't remove the caliper bracket, just pull the caliper, slap in the pads, compress the piston and replace the caliper.

However if you don't do the proper cleaning & lube of the caliper pins, caliper bracket where the SS clips go then you are wasting your time on new pads.

In addition if you don't remove the caliper bracket, then the rotor cannot be removed. The rotor needs to come off, lube the hub and replace the rotor (even if reusing the rotor). Or just that much harder when you do need to replace the rotor.

I dont know what I would do working outside the rust belt, no smoke wrench, drill and taps, no toys to play with.
 
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