Stop Tech BBK: Trouble Removing Pads

[JMK007]

I recently purchased a stop tech bbk, St-60 front, St-40 rear because they are supposed to perform great on track and are easy for swapping pads. Although they have been awesome on track, I have had a great difficulty removing stop tech pads. Thinking it must be my mechanical ineptitude, I had an experienced guy help me. In the end, he had to remove the caliper from the rotor and knock them out. He thought it was just a really tight fit and that the sides of the pads needed to be shaved down a tiny bit. When I tried to remove the stop tech track pads after my track weekend, I had the same problem. This is extremely frustrating. This kit was very expensive and was supposed to be easy for swapping pads. I can't even seem to fit a thin flat head screw driver between the pad and rotor to push the pistons back.

For people with stop tech or even brembo bbks, have you had this kind of trouble? Any suggestions short of completely removing the caliper again? I have looked at a lot of videos on how to take out pads on brembo bbks but can't seem to find any on stop tech. Does anyone know of such a video? I know its a big ask...but if anyone would be willing to make a quick video that would be great. Thank you in advance for any help you guys can provide...

[thorny]

Mine come out pretty easy. Just wiggle them from side to side not letting them to get all jammed. I also use a metal pick to give myself some leverage if they dont want to come out, although most of the time they come out no problem.

I love this feature and certainly you dont have to remove the calipers!

[Transfer]

Something doesn't sound right. I had a stoptech bbk on a different car and they slid in and out without too much fuss.

[Moxie]

Try cracking open the brake resevoir lid, remove the bolts, spread the pads using using a large pliers on the pads tabs to take pressure off the rotors. You open the pliers. They'll pull right out. Pretty easy.

[dmw16]

Did you drive the pads back before trying to remove them? You can use a screw driver or better yet a caliper retraction tool to move the pistons back so you can remove the pads.

This is the one I use: http://buy1.snapon.com/catalog/item....re&dir=catalog

[JMK007]

I will try to the above suggestions later tonight...thanks. According to the vendor who helped me at the track, the issue is the ends of the brake pads. They don't slide in easily but have to be pushed in with some force. Likewise, they have pulled out firmly--or actually knocked out. He felt the paint on sides brake pad ends was just a little to thick. The rotor spins freely so it does not seem like the pistons are a problem. However, I am a little surprised I can fit a flat head screw driver between the pad and rotor. Am I supposed stick the screw driver the little groove area in the brake pad material or on the flat part of the pad. Alternatively, maybe I will try to use the pliers on the brake pad tabs. I will also try other methods suggested (ie., wiggling the pads and knocking from the bottom).

If anyone else has had this problem, has suggestions, or knows of a video, that would be great.

Thanks again...

[paradocs98]

I've found it to be a bit difficult at times, too, but I've had luck doing this:

After removing the bridge, using a pad retraction tool like the Girodisc to spread the pads away from the rotors, thereby pushing the pistons back into the caliper body. The tool pushes on the "ears" or tabs that protrude from the pad backing plates. Then wiggle the pads back and forth gently, and then pull them out with a pair of pliers grasping the edge of the pad backing plate.

If you're using Pagids, they have little holes in the tabs on the pad backing plates. Take something thin and rigid like an ice pick or small hemostat (if you're a medical person) and stick it in the hole, giving yourself leverage to pull the pads out.

Just remember to pump the brake pedal a few times after each corner is done to reseat the pistons on the pads. Don't wait until all four corners are done to do this.

[JAJ]

Originally Posted by JMK007

I recently purchased a stop tech bbk, St-60 front, St-40 rear because they are supposed to perform great on track and are easy for swapping pads. Although they have been awesome on track, I have had a great difficulty removing stop tech pads. Thinking it must be my mechanical ineptitude, I had an experienced guy help me. In the end, he had to remove the caliper from the rotor and knock them out. He thought it was just a really tight fit and that the sides of the pads needed to be shaved down a tiny bit. When I tried to remove the stop tech track pads after my track weekend, I had the same problem. This is extremely frustrating. This kit was very expensive and was supposed to be easy for swapping pads. I can't even seem to fit a thin flat head screw driver between the pad and rotor to push the pistons back.

For people with stop tech or even brembo bbks, have you had this kind of trouble? Any suggestions short of completely removing the caliper again? I have looked at a lot of videos on how to take out pads on brembo bbks but can't seem to find any on stop tech. Does anyone know of such a video? I know its a big ask...but if anyone would be willing to make a quick video that would be great. Thank you in advance for any help you guys can provide...

I ran into this exact problem on a set of ST40 Stoptechs years ago. The problem was the brake pad backing plate, and it had some "flash" on the edges from when it was punched out of a piece of steel plate at the factory. A few minutes with a file and it's all good. As far as I know, Stoptech doesn't deliver that brand of pad any more, but I guess it can happen to any of them.

Also check the pad pockets with the pads out to make sure there's nothing in the way in there, but chances are good it's just a slightly oversize set of pads.

Having said all that - it just occurred to me to wonder - did you buy them used or have them powder coated? Is it possible they've been powder coated and it's the paint that's causing the problem? Powder coating adds a very thick layer of paint, and it could be that as well, particularly if you're having this problem with more than one set of pads.

[MCPilot]

I have(had) this same problem with my new ST60's - both the stock StopTech pads that came with the kit and the Hawk DTC-60's I use at the track were an extremely tight(impossible) fit. To resolve the issue I had to grind the backing plates down quit a bit - once this was done the pads slide in and out easily like the ST-40's I have in the rear.

I had a previous car with ST60's and never had this issue. Because the issue was present with both StopTech and Hawk pads I wonder if a batch of ST60 calipers went out that were a little out of spec?

[JMK007]

The bbk is brand new. I will grind down the backing plates--if I can ever get them out. Will keep you guys posted...

[dmw16]

What brand pad are you using? Are these the Stoptech pads that it came with?

[Moxie]

Originally Posted by JMK007

The bbk is brand new. I will grind down the backing plates--if I can ever get them out. Will keep you guys posted...

You don't have to grind anything - Spread the pads using a spreader or pliers. If they won't spread, take the top off the reservoir to relieve pressure & try spreading them again.

[Sleeper519]

Originally Posted by paradocs98

I've found it to be a bit difficult at times, too, but I've had luck doing this:

After removing the bridge, using a pad retraction tool like the Girodisc to spread the pads away from the rotors, thereby pushing the pistons back into the caliper body. The tool pushes on the "ears" or tabs that protrude from the pad backing plates. Then wiggle the pads back and forth gently, and then pull them out with a pair of pliers grasping the edge of the pad backing plate.

If you're using Pagids, they have little holes in the tabs on the pad backing plates. Take something thin and rigid like an ice pick or small hemostat (if you're a medical person) and stick it in the hole, giving yourself leverage to pull the pads out.

Just remember to pump the brake pedal a few times after each corner is done to reseat the pistons on the pads. Don't wait until all four corners are done to do this.

Sorry to thread jack. Just curious on this, what's the scoop? I've been pumping after all 4 are done...

[JMK007]

Okay - so the issue is what we thought from the beginning. The sides of the backing plates needed to be shaved done ever so slightly. Now the pads slide in and out without problems. Apparently, this can happen with some batches of stop tech pads.

[paradocs98]

Originally Posted by Sleeper519

Sorry to thread jack. Just curious on this, what's the scoop? I've been pumping after all 4 are done...

During pad changes, pushing the pistons back into the caliper bodies pushes the brake fluid column back up toward the brake fluid reservoir. Doing this at each corner probably only raises the level in the reservoir a little bit until you depress the brake pedal and reseat the pistons on the brake pad backing plates. But if you were to wait until all four corners were done before pressing the brake pedal and reseating the pistons, the additive increase in reservoir fluid level could cause the brake fluid to overflow the reservoir. This would especially be a concern if you had recently topped off the reservoir level when your current pad set was fairly worn and the pistons therefore engaged out pretty far toward the rotor faces. The relatively increased distance that you would have to push the pistons back into the calipers during the next pad change, combined with a freshly topped off fluid reservoir, would increase the chance of overflow if you didn't press on the brake pedal and reseat the pistons after doing each corner.

This is what I've read and been told, so it's the way I've always done it. I haven't actually experimented with watching the reservoir level as I do pad changes, but it conceptually makes sense.

[Bubbles]

Originally Posted by paradocs98

During pad changes, pushing the pistons back into the caliper bodies pushes the brake fluid column back up toward the brake fluid reservoir. Doing this at each corner probably only raises the level in the reservoir a little bit until you depress the brake pedal and reseat the pistons on the brake pad backing plates. But if you were to wait until all four corners were done before pressing the brake pedal and reseating the pistons, the additive increase in reservoir fluid level could cause the brake fluid to overflow the reservoir. This would especially be a concern if you had recently topped off the reservoir level when your current pad set was fairly worn and the pistons therefore engaged out pretty far toward the rotor faces. The relatively increased distance that you would have to push the pistons back into the calipers during the next pad change, combined with a freshly topped off fluid reservoir, would increase the chance of overflow if you didn't press on the brake pedal and reseat the pistons after doing each corner.

This is what I've read and been told, so it's the way I've always done it. I haven't actually experimented with watching the reservoir level as I do pad changes, but it conceptually makes sense.

If the brake fluid overflows you can rest assured the vacuum sensor directly underneath will fail if not cleaned immediately and put your car into limp mode. It is the worst location for the sensor and a pain to replace.

[jphughan]

Originally Posted by MCPilot

I have(had) this same problem with my new ST60's - both the stock StopTech pads that came with the kit and the Hawk DTC-60's I use at the track were an extremely tight(impossible) fit. To resolve the issue I had to grind the backing plates down quit a bit - once this was done the pads slide in and out easily like the ST-40's I have in the rear.

I had a previous car with ST60's and never had this issue. Because the issue was present with both StopTech and Hawk pads I wonder if a batch of ST60 calipers went out that were a little out of spec?

I just had my ST-60 installed and encountered the same thing! It applied to both the included pads and the PFC 08 pads I'd purchased for the track, in both calipers. When the pad is oriented vertically as if you're about to insert it into the caliper, it's like the backing plate is too "tall", right? The tech who did my install said he MIGHT have been able to hammer them in (but kind of doubted it), but didn't try because he worried that with a fit that tight the pads might bind. So instead he ground down the backing plates on the included pads and my PFCs.

A rep at StopTech told me that the ST-60 caliper variant specific to the M3 has abutment plates that create a very tight fit by design as an anti-rattle measure, and both the rep and the tech that did my install thought this would become a non-issue after the kit was used for a while -- maybe the current pads will wear down the abutment plates a bit during normal use so the next set fits better? Time will tell, but I hope that proves true because easy pad swaps was a selling point on this kit for me, and if I have to test fit new pads to check clearance prior to needing them and get to a metal grinder to adjust problematic pads, that sort of destroys the whole plug and play aspect. I'm also concerned that if the problem is in fact with the calipers and it won't go away with use, it will be more difficult to get them replaced later. But then again, if this WILL go away with time, I don't really want to insist on replacement calipers now only to have the replacements behave the same way and end up just spending more on labor for the swap and another bleed.

Originally Posted by Bubbles

If the brake fluid overflows you can rest assured the vacuum sensor directly underneath will fail if not cleaned immediately and put your car into limp mode. It is the worst location for the sensor and a pain to replace.

Ugh, I had this issue just during normal driving and not even when swapping pads, total pain. Thankfully it was covered under warranty (they suspected either spillage during a previous bleed or a reservoir overfill that resulted in fluid ejection during driving), but I couldn't believe it when I learned that a sensor that's sensitive to brake fluid was placed directly under the brake fluid reservoir. Then again, my instructor/mechanic's E36 M3 has a coolant hose supported by only a few tiny plastic clips running directly above the blades of the radiator fan....

Originally Posted by JMK007

I recently purchased a stop tech bbk, St-60 front, St-40 rear because they are supposed to perform great on track and are easy for swapping pads.

I have looked at a lot of videos on how to take out pads on brembo bbks but can't seem to find any on stop tech. Does anyone know of such a video? I know its a big ask...but if anyone would be willing to make a quick video that would be great. Thank you in advance for any help you guys can provide...

Out of curiosity, what made you upgrade the rears? I was planning to until I encountered StopTech's own article arguing AGAINST rear brake upgrades in almost every case: http://www.stoptech.com/technical-su...brake-upgrades. I figured if a company that makes money selling brake upgrades is telling you not to buy certain brake upgrades, it was advice worth heeding, and I certainly didn't mind saving a few grand. So at the track I'm going to run track pads up front and keep the Street Performance pads in the stock rear calipers, which others seem to have been doing for a while without any ill effects since the rears perform relatively little braking.

As for the video, I've looked myself unsuccessfully, but the full installation guide contains some good photos and there are some pretty good text descriptions out there, like these two threads:

http://forums.bimmerforums.com/forum...pTech-ST40-BBK

http://my350z.com/forum/brakes-and-s...ptech-bbk.html

[jphughan]

Just to update this thread a bit, a StopTech rep replied to my email about this on July 3rd and said they'd have their Engineering team look into it; I linked this thread. I followed up with that rep a week ago asking whether they'd found anything since I hadn't heard back, and I just emailed him again asking for an update since I didn't hear anything back last week either.

It seems like the people who are affected by this all purchased their kits new at roughly the same time, so it does lead me to believe it might be a bad batch of calipers, but of course I'm still waiting to receive an official word. I will of course report back if and when I do. In the meantime, it might be worth the other people experiencing this issue to reach out to StopTech's support email address to let them know you're affected and would like some sort of resolution.

[JMK007]

Thanks for the update. Please keep us posted.

[bigjae1976]

The tight fit is normal. As mentioned...its an anti-rattle measure. Apply some anti-seize to the metal tabs...that will make it a little easier to get the pads out. The pads will come right out after a couple of changes. If the pads are super tight, I take a screwdriver and pry the pads out from underneath using the rotor hat as a lever point.

Originally Posted by paradocs98

During pad changes, pushing the pistons back into the caliper bodies pushes the brake fluid column back up toward the brake fluid reservoir. Doing this at each corner probably only raises the level in the reservoir a little bit until you depress the brake pedal and reseat the pistons on the brake pad backing plates. But if you were to wait until all four corners were done before pressing the brake pedal and reseating the pistons, the additive increase in reservoir fluid level could cause the brake fluid to overflow the reservoir. This would especially be a concern if you had recently topped off the reservoir level when your current pad set was fairly worn and the pistons therefore engaged out pretty far toward the rotor faces. The relatively increased distance that you would have to push the pistons back into the calipers during the next pad change, combined with a freshly topped off fluid reservoir, would increase the chance of overflow if you didn't press on the brake pedal and reseat the pistons after doing each corner.

The trick is to top off your brake fluid when you put new pads in and the pistons are fully compressed. Never top off...keep the resorvoir at the same level when you bleed the brakes. It will never overflow.

Originally Posted by Bubbles

If the brake fluid overflows you can rest assured the vacuum sensor directly underneath will fail if not cleaned immediately and put your car into limp mode. It is the worst location for the sensor and a pain to replace.

Yup. This happened to a great looking, helluva nice guy who can drive really fast!

[jphughan]

So I couldn't get StopTech to respond to me, but Harold@HPAutowerks (the excellent sponsor on these boards who sold me the BBK) contacted the StopTech rep directly asking about what could be done, and the rep responded, "For replacement calipers, we would send them out as needed."

Not very informative as to the root cause of the issue, but I figured if replacements were being offered, this is an issue that may not go away with time. So I opted for replacements and StopTech will be shipping them out, thankfully before I'm required to ship mine back. Before I pay to have them installed (and write off a bottle of Castrol SRF in the process ), I'm going to take some unaltered pads to check that they fit into the new calipers and do NOT fit into my current ones to be sure that the new calipers are actually different in that regard.

But for anyone else experiencing this issue, you may want to get in touch with the vendor from whom you purchased your kit and ask them to work with StopTech to arrange for replacements. Definitely aggravating to have to replace calipers, but it happens, and I appreciate StopTech shipping replacements first and especially appreciate Harold@HPAutowerks staying persistent on this! Harold has consistently delivered great customer service on this and other orders, and his prices are always the best or very close, so earned another loyal customer here.

I'll report back once I've tested the new calipers.

[JAJ]

I just took delivery of a set of Stoptech brakes for my Mustang - ST60 calipers. Having read this thread (and responded above) I took the calipers out of the packaging and checked the fit of the pads as supplied.

- the pads are 152.00 mm (measured) length. That's EXACTLY on-spec for that pad type.

- the abutment plates - the spring-loaded clips that hold the pads in place end-to-end - are too tight to put the pads in. If you look from the opening of the pad pocket, the clip at the "upper" end of the pocket is bent at slightly less than 90 degrees, making the distance from one plate to the other shorter.

I don't know if this is a manufacturing defect or a design feature, but one way or another, getting pads into these dudes is going to be a challenge. The abutment plates are held in place by a Torx T25 screw, so popping them out and re-bending them might be the best solution.

These pad pockets are simply too tight; even if I can get the pads in, they'll drag because they can't release properly.

UPDATE: So I went back out to the garage and looked more closely at why the pads won't go in. It's easy when you have the calipers in hand and you can take the bridges off and just see how they're put together.

- the abutment plates are stamped stainless steel. When they're made, the stamping machine leaves a burr. Because they're stainless, it's a very hard burr. The burr is on the inside of the pad pocket, and it catches the rough edge of the pad and holds it. Filing off the burr, and filing the corresponding burr off the edges of the pad made the pads slide into the top part of the pad pocket reasonably smoothly. When I started, they just plain weren't going in. So this is progress.

- one abutment plate of the pair that holds each pad is formed with a bump that acts as a spring to keep the pads tight in the pocket. Even when the burrs are gone on all the metal edges, the spring is still pretty tight. I hammered a pad into place with a soft-face hammer and then slid it out through it's operating range (simulating pad wear) with a pry bar. It's really tight in there - it will get looser as the pads hammer the bump down with the force of stopping the car, but that will take a while, and meantime you have to lever the pads out and hammer them back in. Not a good solution. When I had this problem on my ST40's back in 2003, I used a file to cut the bump down a bit. Or I can take the bent abutment plates out and hammer them flat on an anvil. I might just contact Stoptech and see if I can get a set of four "unbent" abutment plates. I've had AP Racing and Brembo's, and they don't have any corresponding design features to this - the pads just go into pockets that are the right size, and that's that.