This began as a simple replacement of brake pads, but was made into more of a project by a few setbacks and the addition of paint.
When I first registered the Subaru and got its out-of-province inspection done, I was warned that the brake pads were a little thin. Not inspection failing thin, but close. I resolved to replace them soon.
Finding brake pads turned out to be a bit of a chore, as you can’t simply walk into your local parts shop and ask for brake pads from a 1996 Japanese-spec Subaru STI version 3. A little research led me in one right direction, and one wrong direction. What I ended up using for the front brakes were pads from a 1996 Nissan 300ZX, and I eventually discovered that the rear brakes are the same as a 1994 Subaru Legacy turbo (though unfortunately that’s not what I ordered).
I would have loved to put on some EBC or Hawk pads, but I just didn’t want to spend $300+ on brake pads. Instead, I found some ceramic pads on Ebay. The ceramic compound should theoretically give good braking characteristics, last a long time, be kind to my rotors, and won’t make the wheels all dirty with brake dust (as compared with traditional brake pads). The cost was $30 each for front and back, including shipping. That’s worth trying out, at least!
I decided that while I was in there, I would give the calipers a quick shot of paint before winter makes them into a big rusty mess. This would add a lot more time to the project than I originally anticipated - but I hear it adds a bunch of horsepower so it’s totally worth it.
The first thing to do, of course, is to get the car up on stands and remove the wheels. Removing the calipers is a little bit different than other cars I have owned due to the non-floating nature of the front calipers and Subaru’s general love of quirkiness (such as flat engines, for instance).
In the front, there isn’t a traditional caliper mounting bracket and caliper, it’s all kind of one big unit. Two big bolts undo the whole thing with no slide pins to worry about. In the rear it does float on a slide pin, but is uncoupled by a single bolt at the back of the caliper, then rotated forward around the front pin until the caliper is free to be pushed off of it. Sorry, no pics of the caliper removal - but it’s really straightforward.
When they’re removed they should be hung by wire or string from the spring above. The rubber brake hoses aren’t meant for the kind of stress imposed by hanging a heavy steel lump from them. It’s one of those things that you can probably get away with for a while, but the consequences could potentially be disastrous if you were to hang a caliper on its hose and put a hole in it. Kind of like jump starting a car by putting the negative cable directly on the battery instead of on another piece of grounded metal. Those sparks are usually harmless, but one day your battery might asplode in your face.
The rear calipers actually sit quite nicely on the rotors and don’t need to be wired up.
Once the calipers were off I decided to tackle the little bit of rust that had already developed on the calipers. The outboard sides of the calipers looked relatively rust-free, but the inboard sides had a good layer of surface rust. First, I hit it with an old, dull wood chisel to scrape off the loose rust.
That was followed with some tedious wire brushing, which got rid of the built-up road grime and a lot of the remaining rust. I could have gone farther and used sand paper to really get the rest but I was already a bit sick of cleaning up calipers. If they were removed from the car it would have been a lot easier, but crouching down in the wheel well and trying not to twist the brake line too much was really tedious! The final step was to hit it with some degreaser and a rag to get off any remaining oils that would keep the paint from sticking.
Masking the wheel wells was really simple because it’s no big deal if you overspray black paint in a black wheel well. I wanted to keep paint off the body, the brake lines, brake discs and that was about it. I used some black barbeque paint left over from another project, as it should be better at resisting the heat of the calipers than other paints.
I gave it lots of light coats, trying my best to flip the caliper around to get it its many nooks and crannies (and yes, I did manage to miss a small spot or two). Again, this would be much much easier on a bench instead of on the car.
When the paint was dry enough to handle it was time to do the pads. The front pads are held captive in the caliper by two pins, and the pins are held in with a wire clip. This clip is easily pushed out of the centre of the caliper and popped out of the pins, freeing them for removal. The pin is pictured below, removed and sitting on top of the caliper. The pins are at the far sides of the caliper opening:
The pins can be tapped out with a hammer and a small punch, which will also free up the brake pads, pad shims, and the anti-rattle clip that rides in the middle of the caliper. Make sure you note the order and orientation of the parts. On my car, the outer pad had only a single solid shim, while the inner pad had one solid shim and one vented shim:
Some brake pads will come with new shims and new grease, but mine did not. I would be reusing both (note to self - next time get some brake grease). The grease helps transfer heat from the pads to the caliper.
New pads versus old:
You can see above that one of the new pads came with a pad wear warning screecher thingy on the bottom, while the old ones are missing that. This small piece of metal will contact the brake disc when the pad is nearly worn away, which makes a terrible screeching noise and is a great reminder to replace your pads! It shouldn’t really matter which side this goes on, but I noticed the old inner pad was a little more worn than the outer one and so I elected to put it on the inside.
To fit the meatier new pads in the calipers, the caliper pistons need to be pushed out so they can fit over the brake disc. The usual method is to put a big c-clamp on the piston and shove it back into the caliper. It’s not strictly necessary to do so, but opening the bleeder screw on the caliper (with a hose to direct the brake fluid into a waste container) will make pushing the piston a little easier, and should theoretically be nicer to the seals in your master cylinder. The block of wood in the picture below is there to be nice to the new caliper paint while squeezing the c-clamp.
Here’s a little trick for opening bleeder screws: use a socket. You generally need a wrench to open and close the screw once it’s free, but a 6-point socket has a much better bite on the screw than either the open end or the 12-point box end of a wrench, making it much less likely to round off. A few taps on the socket wrench handle with a small dead-blow hammer should free most bleeders screws, drama-free.
While pushing the pistons back into the calipers, one of the eight front pistons just would NOT go back in. It was seized. This tends to happen when water collects in the brake system, which causes rust in the calipers. This rust can sometimes weld the metals together, as was the case here. The proper thing to do when this happens is to remove the caliper from the car, completely disassemble it, and rebuild the caliper with new pistons and new seals.
I had no such rebuild kit and I needed the car to be ready, so I used a different method. Breaking the piston free from its seized position would work for at least a while. The c-clamp wouldn’t stay put with enough force to push the piston back, so I made up a small press to do the job. Two pieces of scrap square metal tubing, two bolts, two nuts, and a little drilling and grinding gave me this:
It was applied to the seized piston, tightened, and the piston was broken free:
This fix may last a day, a week, or maybe forever. The brake fluid will definitely need a flush to get rid of that water, however. Note to self: go buy a caliper rebuild kit before it seizes again.
The new pads were installed with the old shims and pins, and the calipers bolted back onto the hubs. Done. On to the rears.
The rear pads are floating in the rear calipers and are pulled out without having to free up any clips or pins. When I pulled mine out and compared them to my new pads, I found this (new pad bottom, old pads top/middle):
One of these things is not like the other. It turns out that I had bought the wrong pads. The old rear pads still had a decent amount of life in them, so I didn’t feel too badly about put them back in instead of new ones. It’s not usually a good idea to have two different kinds of brake pads front and rear as they will heat up and bite differently, but they would work for me temporarily while I got a new set. Back in they went.
The calipers were improved with their new paint…
…but something was missing. A small paintbrush and some white paint I had laying around gave me this:
A smaller brush would have been better, but I used what I had and got a little paint where it wasn’t supposed to go. Still, I’m pleased with the result.
The new pads will need to be pushed into the discs before they can do any braking. A few presses of the brake pedal will usually accomplish this. It’s a good idea to make sure your brake fluid reservoir is filled BEFORE this point.
I didn’t!
My pedal went right to the floor and I introduced a lot of air into my brake lines. If you have never felt brakes with air in them, your foot will go a lot farther to the floor than it should and you won’t get much “stop” when you press the stop pedal.
What followed was a marathon bleeding session at all four tires. I was too disgruntled to take any pictures of this stage, but brake bleeding is a subject that can be easily found on the interwebs if you’re curious.
Even after bleeding all four wheels several times, I wasn’t satisfied with the brake feel. I still felt like there was a little air in there somewhere. Sometimes, when a brake fluid reservoir is accidentally emptied, it can trap air in the master cylinder. What needs to be done in this case is a master cylinder bleeding (usually called “bench bleeding”, though it can be done in-car) followed by another round of caliper bleeding.
The Impreza master cylinder has two outputs, but one is blocked by the STI strut bar. You can see the easily accessed one in the pic below, and the other is hidden in the shadows on the left side of the cylinder:
Removing the strut bar gives tight but sufficient access to the other line:
Those lines need to be carefully removed and pushed aside. It’s a good idea to have something underneath to catch the brake fluid that will drip out. Otherwise, you’ll end up with less paint on your inner fender than you started with.
It’s possible to purchase a “bench bleeding kit” at auto parts stores, but I just made my own out of an old bleeder screw and a cut-off brake line. These screw into the ports that the brake lines were unscrewed from, and some clear vinyl tubing is routed up into the reservoir:
If you haven’t just bled your brakes like crazy and the fluid in the reservoir isn’t new, you should probably put the lines into a bottle of old brake fluid so as to cycle in fresh stuff from the reservoir instead.
A second person sits in the drivers seat and slowly presses the brake pedal. The vinyl tubes are pinched off to prevent fluid (and air) from flowing back through them, then the pedal is slowly released. This is repeated until all bubbles have ceased coming out of the cylinder, just like regular brake bleeding at the caliper.
Be very careful removing the bench bleeding kit from the master cylinder, as getting brake fluid anywhere around there is going to make a nasty mess. Tighten the brake lines back into the master cylinder without too much delay to minimize the amount of fluid lost out of (and potential air introduced into) the master cylinder. Another round of caliper bleeding should finish things off.
If you haven’t also replaced your discs or had them machined (I did neither) then it will take a little while for the pads to “bed in”, which involves the disc and pad wearing into each other until they are touching each other over the full contact surface.
Well, that’s it. What was going to be an afternoon of pad replacement and paint ended up being a whole day of scraping off rust and bleeding the brakes a million times while swearing at my lack of foresight to fill the brake reservoir. Sometimes, easy jobs like brakes can turn into bigger jobs than we expect.
At least I’ve got the extra horsepower from the caliper paint. Weeeeeeeeee!
Cost breakdown:
$30 - cheap ceramic brake pads
$11 - new brake fluid
==$41
Incidental supplies:
wire brushes
paint
masking tape
a wife who doesn’t mind repeatedly pressing a brake pedal in a chilly garage
When I first registered the Subaru and got its out-of-province inspection done, I was warned that the brake pads were a little thin. Not inspection failing thin, but close. I resolved to replace them soon.
Finding brake pads turned out to be a bit of a chore, as you can’t simply walk into your local parts shop and ask for brake pads from a 1996 Japanese-spec Subaru STI version 3. A little research led me in one right direction, and one wrong direction. What I ended up using for the front brakes were pads from a 1996 Nissan 300ZX, and I eventually discovered that the rear brakes are the same as a 1994 Subaru Legacy turbo (though unfortunately that’s not what I ordered).
I would have loved to put on some EBC or Hawk pads, but I just didn’t want to spend $300+ on brake pads. Instead, I found some ceramic pads on Ebay. The ceramic compound should theoretically give good braking characteristics, last a long time, be kind to my rotors, and won’t make the wheels all dirty with brake dust (as compared with traditional brake pads). The cost was $30 each for front and back, including shipping. That’s worth trying out, at least!
I decided that while I was in there, I would give the calipers a quick shot of paint before winter makes them into a big rusty mess. This would add a lot more time to the project than I originally anticipated - but I hear it adds a bunch of horsepower so it’s totally worth it.
The first thing to do, of course, is to get the car up on stands and remove the wheels. Removing the calipers is a little bit different than other cars I have owned due to the non-floating nature of the front calipers and Subaru’s general love of quirkiness (such as flat engines, for instance).
In the front, there isn’t a traditional caliper mounting bracket and caliper, it’s all kind of one big unit. Two big bolts undo the whole thing with no slide pins to worry about. In the rear it does float on a slide pin, but is uncoupled by a single bolt at the back of the caliper, then rotated forward around the front pin until the caliper is free to be pushed off of it. Sorry, no pics of the caliper removal - but it’s really straightforward.
When they’re removed they should be hung by wire or string from the spring above. The rubber brake hoses aren’t meant for the kind of stress imposed by hanging a heavy steel lump from them. It’s one of those things that you can probably get away with for a while, but the consequences could potentially be disastrous if you were to hang a caliper on its hose and put a hole in it. Kind of like jump starting a car by putting the negative cable directly on the battery instead of on another piece of grounded metal. Those sparks are usually harmless, but one day your battery might asplode in your face.
The rear calipers actually sit quite nicely on the rotors and don’t need to be wired up.
Once the calipers were off I decided to tackle the little bit of rust that had already developed on the calipers. The outboard sides of the calipers looked relatively rust-free, but the inboard sides had a good layer of surface rust. First, I hit it with an old, dull wood chisel to scrape off the loose rust.
That was followed with some tedious wire brushing, which got rid of the built-up road grime and a lot of the remaining rust. I could have gone farther and used sand paper to really get the rest but I was already a bit sick of cleaning up calipers. If they were removed from the car it would have been a lot easier, but crouching down in the wheel well and trying not to twist the brake line too much was really tedious! The final step was to hit it with some degreaser and a rag to get off any remaining oils that would keep the paint from sticking.
Masking the wheel wells was really simple because it’s no big deal if you overspray black paint in a black wheel well. I wanted to keep paint off the body, the brake lines, brake discs and that was about it. I used some black barbeque paint left over from another project, as it should be better at resisting the heat of the calipers than other paints.
I gave it lots of light coats, trying my best to flip the caliper around to get it its many nooks and crannies (and yes, I did manage to miss a small spot or two). Again, this would be much much easier on a bench instead of on the car.
When the paint was dry enough to handle it was time to do the pads. The front pads are held captive in the caliper by two pins, and the pins are held in with a wire clip. This clip is easily pushed out of the centre of the caliper and popped out of the pins, freeing them for removal. The pin is pictured below, removed and sitting on top of the caliper. The pins are at the far sides of the caliper opening:
The pins can be tapped out with a hammer and a small punch, which will also free up the brake pads, pad shims, and the anti-rattle clip that rides in the middle of the caliper. Make sure you note the order and orientation of the parts. On my car, the outer pad had only a single solid shim, while the inner pad had one solid shim and one vented shim:
Some brake pads will come with new shims and new grease, but mine did not. I would be reusing both (note to self - next time get some brake grease). The grease helps transfer heat from the pads to the caliper.
New pads versus old:
You can see above that one of the new pads came with a pad wear warning screecher thingy on the bottom, while the old ones are missing that. This small piece of metal will contact the brake disc when the pad is nearly worn away, which makes a terrible screeching noise and is a great reminder to replace your pads! It shouldn’t really matter which side this goes on, but I noticed the old inner pad was a little more worn than the outer one and so I elected to put it on the inside.
To fit the meatier new pads in the calipers, the caliper pistons need to be pushed out so they can fit over the brake disc. The usual method is to put a big c-clamp on the piston and shove it back into the caliper. It’s not strictly necessary to do so, but opening the bleeder screw on the caliper (with a hose to direct the brake fluid into a waste container) will make pushing the piston a little easier, and should theoretically be nicer to the seals in your master cylinder. The block of wood in the picture below is there to be nice to the new caliper paint while squeezing the c-clamp.
Here’s a little trick for opening bleeder screws: use a socket. You generally need a wrench to open and close the screw once it’s free, but a 6-point socket has a much better bite on the screw than either the open end or the 12-point box end of a wrench, making it much less likely to round off. A few taps on the socket wrench handle with a small dead-blow hammer should free most bleeders screws, drama-free.
While pushing the pistons back into the calipers, one of the eight front pistons just would NOT go back in. It was seized. This tends to happen when water collects in the brake system, which causes rust in the calipers. This rust can sometimes weld the metals together, as was the case here. The proper thing to do when this happens is to remove the caliper from the car, completely disassemble it, and rebuild the caliper with new pistons and new seals.
I had no such rebuild kit and I needed the car to be ready, so I used a different method. Breaking the piston free from its seized position would work for at least a while. The c-clamp wouldn’t stay put with enough force to push the piston back, so I made up a small press to do the job. Two pieces of scrap square metal tubing, two bolts, two nuts, and a little drilling and grinding gave me this:
It was applied to the seized piston, tightened, and the piston was broken free:
This fix may last a day, a week, or maybe forever. The brake fluid will definitely need a flush to get rid of that water, however. Note to self: go buy a caliper rebuild kit before it seizes again.
The new pads were installed with the old shims and pins, and the calipers bolted back onto the hubs. Done. On to the rears.
The rear pads are floating in the rear calipers and are pulled out without having to free up any clips or pins. When I pulled mine out and compared them to my new pads, I found this (new pad bottom, old pads top/middle):
One of these things is not like the other. It turns out that I had bought the wrong pads. The old rear pads still had a decent amount of life in them, so I didn’t feel too badly about put them back in instead of new ones. It’s not usually a good idea to have two different kinds of brake pads front and rear as they will heat up and bite differently, but they would work for me temporarily while I got a new set. Back in they went.
The calipers were improved with their new paint…
…but something was missing. A small paintbrush and some white paint I had laying around gave me this:
A smaller brush would have been better, but I used what I had and got a little paint where it wasn’t supposed to go. Still, I’m pleased with the result.
The new pads will need to be pushed into the discs before they can do any braking. A few presses of the brake pedal will usually accomplish this. It’s a good idea to make sure your brake fluid reservoir is filled BEFORE this point.
I didn’t!
My pedal went right to the floor and I introduced a lot of air into my brake lines. If you have never felt brakes with air in them, your foot will go a lot farther to the floor than it should and you won’t get much “stop” when you press the stop pedal.
What followed was a marathon bleeding session at all four tires. I was too disgruntled to take any pictures of this stage, but brake bleeding is a subject that can be easily found on the interwebs if you’re curious.
Even after bleeding all four wheels several times, I wasn’t satisfied with the brake feel. I still felt like there was a little air in there somewhere. Sometimes, when a brake fluid reservoir is accidentally emptied, it can trap air in the master cylinder. What needs to be done in this case is a master cylinder bleeding (usually called “bench bleeding”, though it can be done in-car) followed by another round of caliper bleeding.
The Impreza master cylinder has two outputs, but one is blocked by the STI strut bar. You can see the easily accessed one in the pic below, and the other is hidden in the shadows on the left side of the cylinder:
Removing the strut bar gives tight but sufficient access to the other line:
Those lines need to be carefully removed and pushed aside. It’s a good idea to have something underneath to catch the brake fluid that will drip out. Otherwise, you’ll end up with less paint on your inner fender than you started with.
It’s possible to purchase a “bench bleeding kit” at auto parts stores, but I just made my own out of an old bleeder screw and a cut-off brake line. These screw into the ports that the brake lines were unscrewed from, and some clear vinyl tubing is routed up into the reservoir:
If you haven’t just bled your brakes like crazy and the fluid in the reservoir isn’t new, you should probably put the lines into a bottle of old brake fluid so as to cycle in fresh stuff from the reservoir instead.
A second person sits in the drivers seat and slowly presses the brake pedal. The vinyl tubes are pinched off to prevent fluid (and air) from flowing back through them, then the pedal is slowly released. This is repeated until all bubbles have ceased coming out of the cylinder, just like regular brake bleeding at the caliper.
Be very careful removing the bench bleeding kit from the master cylinder, as getting brake fluid anywhere around there is going to make a nasty mess. Tighten the brake lines back into the master cylinder without too much delay to minimize the amount of fluid lost out of (and potential air introduced into) the master cylinder. Another round of caliper bleeding should finish things off.
If you haven’t also replaced your discs or had them machined (I did neither) then it will take a little while for the pads to “bed in”, which involves the disc and pad wearing into each other until they are touching each other over the full contact surface.
Well, that’s it. What was going to be an afternoon of pad replacement and paint ended up being a whole day of scraping off rust and bleeding the brakes a million times while swearing at my lack of foresight to fill the brake reservoir. Sometimes, easy jobs like brakes can turn into bigger jobs than we expect.
At least I’ve got the extra horsepower from the caliper paint. Weeeeeeeeee!
Cost breakdown:
$30 - cheap ceramic brake pads
$11 - new brake fluid
==$41
Incidental supplies:
wire brushes
paint
masking tape
a wife who doesn’t mind repeatedly pressing a brake pedal in a chilly garage
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