Check Your Brake Caliper for Binding

[booster]

Originally Posted by peteco

Agree, replacing bellows is best. The "adapter" you refer to; is that the caliper mounting bracket? If so then yes, that is good to remove for another reason also: to lube the wheel bearings. Read the discussion below. This is very important on our heavy Chevy's. There are other discussions on the internet regarding the importance of lubing bearings on the Chevy Silverado, Express, and other GM vehicles that used sealed front bearings. Now is the time to do it when you are in there.

https://www.classbforum.com/forums/f...ings-2305.html

Yep that was a good discussion we had back then. Yes the adapter is bracket that holds the pads and the caliper.


I give ours grease every couple of years, still nice and tight.


Did the sleeves come off the pins on yours like ours did?

[Roadtreker357]

I decided I could not wait until next week to dig into this, on our 2007, Chevy 3500 Roadtrek 210. I have removed the caliper on one side, as well as the bracket that holds the caliper.

I have been thinking about going to semi-metallic pads and drilled and/or slotted rotors (have saved info on what others used). This seems like an opportune time since the front end is apart. The RT has 168,000 miles on the original pads. You can see in the photo that there is lots of pad material remaining, which has delayed my getting new pads/rotors. But the time seems right to do it now.

I am a 'do it myself' type of guy, and not afraid to jump into something. However, I am ignorant on how to go about cleaning out the old lube I used. I hope you will bear with me with a barrage of questions.

1. What is the proper name of the D-shaped bracket that holds the caliper?
2. If I buy a new D-shaped bracket will it come with needed rubber seals so I don't have to remove, clean and install these?
3. If I get a new D-shaped bracket, will I be able to reuse the existing caliper?
4. If I must clean out the old lube, what is the method for removing the rubber bellows you see and anything else inside the bracket?
5. Does getting new rotor and pads have anything to do with the above, or is it entirely an independent part of the job?

Thanks in advance for your thoughts,

[booster]

Originally Posted by Roadtreker357

I decided I could not wait until next week to dig into this, on our 2007, Chevy 3500 Roadtrek 210. I have removed the caliper on one side, as well as the bracket that holds the caliper.

I have been thinking about going to semi-metallic pads and drilled and/or slotted rotors (have saved info on what others used). This seems like an opportune time since the front end is apart. The RT has 168,000 miles on the original pads. You can see in the photo that there is lots of pad material remaining, which has delayed my getting new pads/rotors. But the time seems right to do it now.

I am a 'do it myself' type of guy, and not afraid to jump into something. However, I am ignorant on how to go about cleaning out the old lube I used. I hope you will bear with me with a barrage of questions.

1. What is the proper name of the D-shaped bracket that holds the caliper?
2. If I buy a new D-shaped bracket will it come with needed rubber seals so I don't have to remove, clean and install these?
3. If I get a new D-shaped bracket, will I be able to reuse the existing caliper?
4. If I must clean out the old lube, what is the method for removing the rubber bellows you see and anything else inside the bracket?
5. Does getting new rotor and pads have anything to do with the above, or is it entirely an independent part of the job?

Thanks in advance for your thoughts,

Yes on high end semi metallic pads, they will work much better. I would skip the drilled and slotted and go with either high quality plain or very lightly slotted rotors. Hawk even says not to use the their drilled and slotted rotors on heavy duty applications and more and more data is showing plain to be just a good or better and more durable.


Most people I have heard speak of those kind of parts have use the term adapter, but I see on Rock Auto they are called brackets. The adapter term may be because most of the dealing I have had related to the parts were for high perf upgrades where they sell commonly used caliper with different adapters for different vehicles. The ones on Rock Auto do not have the bellows and bushings installed and are remanufactured. You can reuse the caliper if the piston moves OK when you push it in and there are no leaks. If you don't have the pistons blocked with something right now you probably should do it. C clamps of pieces of wood work fine. If you don't some vehicles will hydraulically push the pistons out of the bore, which not a good thing. I don't know if the vans are one that would, but not worth the chance.



I used big wooden handle cotton swabs that are probably 3/8" across and 6" long, with mineral spirits. It takes few fill it up and swab cycles. Once most cleaned I would fill up a hole, they are blind, about half way and shake like crazy. This would get almost the everything with about 3 cycles. To get anything on the very bottom a shot of Gumout aerosol did the trick. That is very tenacious grease to say the least. If you haven't gotten the rubber sleeves out of the holes first, the solvent will like make it much worse by turning them to mush, but it might also melt them completely if let sit long enough.


Rotors and pads would be independent of this issue, I would think. Be sure to check the rotor runout when you put on either the old or new rotors, especially if the inside of the rotor or hub are showing any rust. Try to stay under .003" total runout. You will need and indicator to do that check, however. Put the factory lug nuts on upsidedown if the they are open ended and torque evenly to at least 1/3 of used torque with the wheel on so it pulled down even and tight for checking. Have the caliper and pads off at this point.

[peteco]

Originally Posted by Roadtreker357

I decided I could not wait until next week to dig into this, on our 2007, Chevy 3500 Roadtrek 210. I have removed the caliper on one side, as well as the bracket that holds the caliper.

I have been thinking about going to semi-metallic pads and drilled and/or slotted rotors (have saved info on what others used). This seems like an opportune time since the front end is apart. The RT has 168,000 miles on the original pads. You can see in the photo that there is lots of pad material remaining, which has delayed my getting new pads/rotors. But the time seems right to do it now.

I am a 'do it myself' type of guy, and not afraid to jump into something. However, I am ignorant on how to go about cleaning out the old lube I used. I hope you will bear with me with a barrage of questions.

1. What is the proper name of the D-shaped bracket that holds the caliper?
2. If I buy a new D-shaped bracket will it come with needed rubber seals so I don't have to remove, clean and install these?
3. If I get a new D-shaped bracket, will I be able to reuse the existing caliper?
4. If I must clean out the old lube, what is the method for removing the rubber bellows you see and anything else inside the bracket?
5. Does getting new rotor and pads have anything to do with the above, or is it entirely an independent part of the job?

Thanks in advance for your thoughts,

Agree on all Booster comments. The fact your OEM pads lasted so long is a testament to the "hardness" of the brake material. My pads looked barely worn when I replaced at 50k miles. But this is not a good thing. I was never happy with the stopping power of the OEM brakes. The high performance aftermarket pads stop the vehicle MUCH better. So now is a good time for this safety upgrade as well.

[Roadtreker357]

Booster, at one time you mentioned the StopTech slotted rotors and Hawk STS pads. Links to each.

https://www.amazon.com/StopTech-126-...6556152&sr=8-1

https://www.amazon.com/StopTech-126-.../dp/B001KQBJ2G

https://www.amazon.com/Hawk-Performa...t+Express+3500

If not these slotted rotors, whose should I look at?

You mentioned having the runout checked. Never had that done before. is there much of a downside to not doing this check? To do the check, I would have to put it all together and drive it to some shop to do that for me, right? Sure hate to show my ignorance on such things, but that is how I learn
07C210P

[booster]

Originally Posted by Roadtreker357

Booster, at one time you mentioned the StopTech slotted rotors and Hawk STS pads. Links to each.

https://www.amazon.com/StopTech-126-...6556152&sr=8-1

https://www.amazon.com/StopTech-126-.../dp/B001KQBJ2G

https://www.amazon.com/Hawk-Performa...t+Express+3500

If not these slotted rotors, whose should I look at?

You mentioned having the runout checked. Never had that done before. is there much of a downside to not doing this check? To do the check, I would have to put it all together and drive it to some shop to do that for me, right? Sure hate to show my ignorance on such things, but that is how I learn
07C210P

I think those rotors are "least slotted" ones that are available now, since the Hark old style rotors went away. Those would work fine if slotted is preferred I do still think. I wouldn't use ones with more surface area missing and would prefer, if available, less and more randomly spaced slots for heavy duty use.


That said, we have seen people reuse or buy new OEM (Delco) spec unslotted or drilled rotors and they seem to be doing well. I think most of the major brand alloyed cast iron HD rotors would be worth using as they about 1/2 the cost of the high performance stuff and very possibly use the same castings. The only ones I have used lately were for DWs CRV which I put all four on with Centric coated premium line and they have been very good, ran straight, etc. I think the OEM Delco replacements, Bendix HD, Raybestos HD, etc would probably all do OK, and I am sure others but without any feedback we don't really know. We are learning that the pads are the most important part of all this more and more, as long as they aren't the cheapo rotors. Rock Auto has them for in the $60 range. Be sure to get the correct ones for your unit as the rear rotors are different between the 10" locking full floater unit and the 9.75" semi floater. The is a thread on the forum that lists the dimensions to check to tell from the old rotors. IIRC the 10' axle has a bigger center hole and deeper hat, but best to check.


I like the Hawk pads but you might want to look at Pete's thread on loose shims on his. We have not had that issue but have less miles and no rusting on ours. People have used the heavy duty bendix and Raybesto semi metallics also with no complaints.


For runout, it would be a pain to get them checked and not particularly cheap. You may be able to get a Harbor Freight indicator and magnetic base cheaper, it would be good enough for this check. You can clamp a piece of steel to the bracket, very close to the rotor surface and use feeler gauges, if you have them. They also very inexpensive to get. I try to always check the runout whenever I put rotors back, especially if there is any rust anywhere, as the designs are very prone to crap falling between the rotor and hub as you assemble. You can get a very rough test of the rotor trueness once the pads are broken in well. Just very slowly roll up to a stop with as light a pressure on the pedal as you can while still slowing down. You probably will feel a bit or grab/release in the van speed. A very small amount is pretty normal, it should be very subtle, That is why you are always best to put lug nuts on the rotor right, check the runout, and leave the nuts on until the rest is all assembled. Once the pads are pushed up against the rotor when done by stepping on the pedal, they will hold the rotor quite tight so you can remove the nuts to put on the wheel.

[Roadtreker357]

Thank you Booster for your detailed response, as well as responses received from others earlier today. I will study all the suggestions and do something. Will post what I decide, before ordering.

I just used Coleman fluid to clean out the bracket slide holes. I used a long screwdriver and strips of cloth over the screwdriver to push in and twist around. Using a flashlight, they look pretty clean.

The outer flexible boot is still in place. I don't see how to remove it without destroying it. As the photo earlier today shows, it appears to be in good shape and can still seal on the pin. I might just leave it at that. will search YouTube for a video on brake jobs to see what I can learn there.

[booster]

Originally Posted by Roadtreker357

Thank you Booster for your detailed response, as well as responses received from others earlier today. I will study all the suggestions and do something. Will post what I decide, before ordering.

I just used Coleman fluid to clean out the bracket slide holes. I used a long screwdriver and strips of cloth over the screwdriver to push in and twist around. Using a flashlight, they look pretty clean.

The outer flexible boot is still in place. I don't see how to remove it without destroying it. As the photo earlier today shows, it appears to be in good shape and can still seal on the pin. I might just leave it at that. will search YouTube for a video on brake jobs to see what I can learn there.

What did the rubber sleeve on pin look like? Did it come out with the pin? I can't imagine that still being OK after being right in with the grease. Ours were destroyed in a year.


This is the bushing kit, they small tubular sleeve go over the smaller diameter end of the pin. I don't see them in your pix so they were either missing or still in the holes.


https://www.amazon.com/ACDelco-172-2.../dp/B00557RHXQ


The aftermarket brands on Rock Auto are about $4.

[peteco]

booster: what do you think about this. Check the present rotors for thickness and runout. If they are good then why not continue to use them? I say this because of my earlier comment about so many Chinese replacement parts these days. Many of the replace parts are not US made. I just checked the boxes I kept (with my original rotors in them) for my 9 year old Hawk rotors; they were made in China. I have been happy with the rotors but if they ever need replacing I will check the originals and, if good, will use them. Also, I had only replaced the front rotors, and kept the original rear rotors on the vehicle.

[booster]

Originally Posted by peteco

booster: what do you think about this. Check the present rotors for thickness and runout. If they are good then why not continue to use them? I say this because of my earlier comment about so many Chinese replacement parts these days. Many of the replace parts are not US made. I just checked the boxes I kept (with my original rotors in them) for my 9 year old Hawk rotors; they were made in China. I have been happy with the rotors but if they ever need replacing I will check the originals and, if good, will use them. Also, I had only replaced the front rotors, and kept the original rear rotors on the vehicle.

I did mention that possibility and I still think it would be OK as it has proven to work by others. We also ran the OEM rear rotors that came with the van until the axle swap and they were fine. Unfortunately, he doesn't have the tools to measure them so would need to rent or find a machinist, I think, to borrow them. Either way, the surface will need to be heavily sanded to get a good texture for pad break in as they are probably quite polished from the ceramic pads.


I highly doubt that the pads are original at 168K miles and still that thick, so they likely have been replaced at least once. The rotors also are unlikely the originals, but would have to look to see if they are identified on them. The pads do seem to show numbers, so that could be checked possibly to find out what they really are.


Of interest in the pics is how the rotor is sitting on the hub, as in very crooked. This is exactly what can cause runout from debris as mentioned earlier, if the wheel were just put back on after being like that and not thoroughly cleaned up. There is quite a bit of rust on all of it so cleanup of a lot things will be required most likely. Rust under the pad slide inserts will make the pads stick also need to be cleaned and greased under on on the inserts.


I start to wonder if some past repair put new some new parts in and lost the rubber sleeves on the pins as they may be missing in action per the discussion.

[Roadtreker357]

Originally Posted by peteco

booster: what do you think about this. Check the present rotors for thickness and runout. If they are good then why not continue to use them?

That is what I was thinking of doing. With so little pad wear, the rotors must not be too worn. I need to get the minimum thickness and a mic to see what I have.

Booster asked about the boot. my earlier photo #103 shows the boot on the caliper bracket. Seems to be in good shape to me. Don't know about the status of the bushing. it is pressed in. I found this 27 min video where the bracket is rebuilt. He used an air hammer gun to install the boot. I would have to struggle with a socket and hammer.

https://www.youtube.com/watch?v=4gPf-74EVlY

[booster]

Originally Posted by Roadtreker357

That is what I was thinking of doing. With so little pad wear, the rotors must not be too worn. I need to get the minimum thickness and a mic to see what I have.

Booster asked about the boot. my earlier photo #103 shows the boot on the caliper bracket. Seems to be in good shape to me. Don't know about the status of the bushing. it is pressed in. I found this 27 min video where the bracket is rebuilt. He used an air hammer gun to install the boot. I would have to struggle with a socket and hammer.

If you look at link to the bushing kit, the little rubber pieces that go on the end of the pin are split and go on the small end of the pin. I was not talking about the boots which are can mounted and press in. I did mine by using small chisel to pry them up dent the can to loosen. I them back with a socket and hammer also not bad to do with brackets out.


Have you managed to find the split rubber pieces? If not swelled, they are a snug slip fit on the pin and in the bore, so not pressed and being split easy to put on the pins before insertion into the holes. You would be able to hook them with a pick and pull them out pretty easily if they aren't swollen a soggy like ours were which makes them very hard to get out of the bores as they are way down at the bottom.

[peteco]

Originally Posted by Roadtreker357

That is what I was thinking of doing. With so little pad wear, the rotors must not be too worn. I need to get the minimum thickness and a mic to see what I have.

Booster asked about the boot. my earlier photo #103 shows the boot on the caliper bracket. Seems to be in good shape to me. Don't know about the status of the bushing. it is pressed in. I found this 27 min video where the bracket is rebuilt. He used an air hammer gun to install the boot. I would have to struggle with a socket and hammer.

The bushing is not pressed in, it just slides in. But when swelled it is harder to get out. I did not have as much trouble getting them out as shown in the video. The lube in the video is green colored like the Permatex I used. If so, he is going to have swelling problems.

I started with a socket and hammer for the boot install. I got one in, and then damaged the next one. I then used a piece of PVC pipe and a clamp to press the boot in. I got another one in, then damaged another. So then I used a woodworking clamp on the PVC to try to press the boot in, but they would not go. I had read someone had to file some of metal boot collar off to get it in, so that's what I did. It took clamping and some hammering too. Not very elegant and I would devise a better press setup next time (hopefully never).

[booster]

Originally Posted by Roadtreker357

That is what I was thinking of doing. With so little pad wear, the rotors must not be too worn. I need to get the minimum thickness and a mic to see what I have.

Booster asked about the boot. my earlier photo #103 shows the boot on the caliper bracket. Seems to be in good shape to me. Don't know about the status of the bushing. it is pressed in. I found this 27 min video where the bracket is rebuilt. He used an air hammer gun to install the boot. I would have to struggle with a socket and hammer.

If you look at link to the bushing kit, the little rubber pieces that go on the end of the pin are split and go on the small end of the pin. I was not talking about the boots which are can mounted and press in. I did mine by using small chisel to pry them up dent the can to loosen. I them back with a socket and hammer also not bad to do with brackets out.


Have you managed to find the split rubber pieces? If not swelled, they are a snug slip fit on the pin and in the bore, so not pressed and being split easy to put on the pins before insertion into the holes. You would be able to hook them with a pick and pull them out pretty easily if they aren't swollen a soggy like ours were which makes them very hard to get out of the bores as they are way down at the bottom.

[Roadtreker357]

What I see is exactly like Peteco says and exactly like in the video.

[booster]

Originally Posted by Roadtreker357

What I see is exactly like Peteco says and exactly like in the video.

So you found the two small cylinders of split rubber? Were they still on the pins when you took them out? If not how did you get them out of the holes? It is the part he has in his hand at 7:20 of the video and spent the previous minute trying to get it out.

[booster]

Originally Posted by peteco

The bushing is not pressed in, it just slides in. But when swelled it is harder to get out. I did not have as much trouble getting them out as shown in the video. The lube in the video is green colored like the Permatex I used. If so, he is going to have swelling problems.

I started with a socket and hammer for the boot install. I got one in, and then damaged the next one. I then used a piece of PVC pipe and a clamp to press the boot in. I got another one in, then damaged another. So then I used a woodworking clamp on the PVC to try to press the boot in, but they would not go. I had read someone had to file some of metal boot collar off to get it in, so that's what I did. It took clamping and some hammering too. Not very elegant and I would devise a better press setup next time (hopefully never).

I used a socket to get the bushing started squarely, but it quickly would start to tilt as I tried to get it in further, so I switched to a 1/4" flat end drift punch and did the tap, tap, tap routine around the actual perimeter of the bushing can flange. Once I figured out which spots were the tight spots I could concentrate on them and went much more easily. I was lucky and didn't wreck any, but I think I might have if I hadn't switched to the punch.


The one thing I probably should have tried would be to turn the bellows part inside out down the hole, it that is even possible to do, as then you could press it in with a full flat ram in a press or a vice and it would likely stay straighter.

[Roadtreker357]

Originally Posted by booster

So you found the two small cylinders of split rubber? Were they still on the pins when you took them out? If not how did you get them out of the holes? It is the part he has in his hand at 7:20 of the video and spent the previous minute trying to get it out.

I have not yet tried to remove the rubber bushing, nor the rubber boot. will do that today. Might have to first purchase picks, Monday. No rubber came out with the pins. Thanks to all for the various installation tips.

I do have the service manual and found the minimum rotor thickness, will measure the thickness today, best I can without a mic. Just have a vernier caliper used for measuring cartridge length. The rust on the outer edge of the rotor might interfere with the vernier caliper (reading larger than actual).

[booster]

Originally Posted by Roadtreker357

I have not yet tried to remove the rubber bushing, nor the rubber boot. will do that today. Might have to first purchase picks, Monday. No rubber came out with the pins. Thanks to all for the various installation tips.

I do have the service manual and found the minimum rotor thickness, will measure the thickness today, best I can without a mic. Just have a vernier caliper used for measuring cartridge length. The rust on the outer edge of the rotor might interfere with the vernier caliper (reading larger than actual).

Aside the minimum thickness, you should be looking for maximum variation in thichness of the rotor. Many specs give the three numbers, minimum thickness, maximum runout, and maximum thickness variation. The variation is normally the smallest allowed, and probably at .002". Calipers usually have a relieved area where the jaws meet the beam, so it might bridge the rust, if not just take a file to the rust. Calipers can be really tough to get accurate enough for this measurement, but at least the actual number isn't all that important for the variation, only range so better to that extent. I would not hold the caliper in the normal one handed, slide with the thumb to close style as the can be very hard to get to lie with totally flat contact on long parallel surfaces like you are talking about. Clamp the rotor down or in a vise so it is stable and either reach in over the jaws with one or even two hands to squeeze the jaws themselves onto the surface, slightly wiggling as you squeeze to get it down tight on the entire jaw surfaces. Once down and squeezed tight you probably will be able to feel it stabilize. The hard part may be trying to read the vernier scale while doing this routine so take that into consideration when you set up to do it. Base accuracy on a good quality vernier was normally considered .001 to .002" back in the day when they were all that was available for at the machine measurements in machine shops, with repeatability a bit better closer to .001", but extremely operator dependent. I was always amazed that the old timer (I was in my 20s then) toolmakers could read them to .001 in seconds and always be within +/- .001 of what inspection would get with the Cadillac height gauge on the surface plate.



It is rare to find a person that has a vernier caliper, much less know how to read one. Most non digital and non dial ones now don't even have the vernier scale so just a ruler with jaws, and often plastic or fiberglass. At my last job, which I started in 2013, there were about 100 employees including 3 other engineers and a couple of chemists. They had a beautiful 24" Etalon vernier caliper for measuring machine aligning and setup stuff, and nobody in the building knew how to read it. They would have to hire millwrights to come in and do the setups because of that.


A reminder to those that have digitals that may read to as fine as .0001". Don't believe that they are accurate to the .0001", as the base accuracy is still about the same .001 to .002", although if they are tight, you might find some with quite good repeatability in the .0005" area. Good dial calipers from past times like Tesa, Etalon, Starrett, and some Mitutoyos will also repeat to .0005. I still have 2 Tesas, one more worn that is used for at the machine stuff and one better for tighter stuff in clean area, and two Chinese, but not too bad, copies of the Tesa that I use for scribing and welding setup as they take a beating and the work is non critical. I don't care for the digitals, personally, as I find them hard to use for some things like roundness checks and such, plus I always bump the "zero" button and wind up with bad measurements.

[Roadtreker357]

I used the wrong nomenclature, when saying vernier caliper in a generic sense. The measuring device I actually have is an RCBS electronic digital caliper. Thanks for the tips on how to do the measuring and for looking for thickness variation. Will report back my findings.