Check Your Brake Caliper for Binding

[Roadtreker357]

A quick update. Hawk pads for the front delivered today (07 Express 3500). Still do not have the bushings, nor the machinist gauge for measuring runout. Should have all in hand next week.

The OEM brake pads had wear indicator metal tabs on both the outside and inside pads. The four new Hawk pads have wear indicators on only two pads. I took a photo before removing a caliper and it shows the outside metal tab at the bottom of the pad. Unfortunately I did not notice the orientation of the wear indicator on the inside brake pad, and I have removed pads from both sides. But I did keep the pads paired up, and determined that the inside pad must have had the wear indicator on the bottom also.

From an internet search it appears that when there is only one wear indicator in a pair of pads, it should be placed on the inside position, the side the piston pushes on. Looking at the used pads, the inside pad does have slightly more wear than the mating outside pad.

So, when I finally get to reassemble the brakes, I plan to put the new pad with the wear indicator on the inside, with indicator at the bottom. If any think this is a mistake, please comment.

[booster]

We just got back from a "sanity ride" in the Roadtrek. A bit over 300 miles on a scenic St Croix river loop we often take when we can. All 2 lane, curvy, hilly, lots of little towns, etc. Works well in these times as the only stop was one stop to fill the gas tank. Never out of the van after that as with a bathroom and battery power for the lunch out of the microwave, so no risk or broken rules. Lots of police out enforcing speeding, though, and they were all over the place.

Brakes worked well with the rework done, but didn't really notice anything obviously different. It had been since last year that I had driven it so hard to directly remember. If anything maybe a bit smoother on application and release, but that could be placebo effect.
We got 15.5mpg for the entire day so about what we would expect for that trip on pretty soft tires because it was cold in the 30s all day.

[Roadtreker357]

The boots and bushings arrived today. Just greased the bushings and pushed them to the bottom with a flat screw driver. That was the simple installation.

To drive the boots into the bore, the caliper bracket was put in a vice. Used deep sockets, 3/4" and 13/16". Was easier to get the boot inside the larger socket, but this socket is a little too big for the flange, but worked to start with. Put some silicone spray in the smaller socket and with the help of a screwdriver, the bellows was stuffed into the socket. th3 3/4" socket fits the flange pretty good. Took a little finesse tapping the socket on the high side when needed. Once half way in it lined up and was fairly straight forward to tap in the rest of the way,

Don't ask me how I know that the bellows can be pinched between the 3/4" socket and the flange when tapping, resulting in a cut in the rubber, and a trip to AutoZone.

Caliper brackets are ready to install. Rotors are on the hubs. Still waiting on the machinist gauge for determining lateral run-out.

[Roadtreker357]

The machinist gauge arrived today. The most time consuming part of determining run-out was finding a place for the base magnet that allowed the gauge to be positioned perpendicular to the rotor. My gauge is in 0.0005" increments, so two tick marks is 0.001". That is the run-out I determined on each front rotor. BTW, I did replace both front wheel bearing modules 90,000 miles ago before going with OEM steel wheels.

This is the gauge I bought: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Took the RT for a drive to follow the bed-in procedure; 8 moderate braking from 30-35 mph and two hard braking from 40-45 mph. Not coming to a complete stop on any of those runs.

I want to thank each of you that contributed your knowledge to this project. It would not have gone as well in the absence of the nuggets of knowledge this forum provided. If any one wants to tackle this and has questions, I will be happy to assist.

[Roadtreker357]

I just cleaned and greased the rear slide pins, nothing appeared damaged. Did not change the OEM pads, but did sand them some to remove glaze.

One tactical error; I did not realize one of the slide pins has ridges along its length, so did not know it came from the top or bottom of the caliper. Only had the right wheel off the ground. Gambled and put that slide at the top of the caliper. When I did the left side, the ridged pin was on the bottom. I did look in the bores and did not detect any difference.

Does it really make any difference where this slide pin with ridges is placed? If so, is the bottom the correct location for both rear brakes? 2007 Express 3500 (Roadtrek). 30 minutes of searching the web did not yield an answer,

[peteco]

Originally Posted by Roadtreker357

I just cleaned and greased the rear slide pins, nothing appeared damaged. Did not change the OEM pads, but did sand them some to remove glaze.

One tactical error; I did not realize one of the slide pins has ridges along its length, so did not know it came from the top or bottom of the caliper. Only had the right wheel off the ground. Gambled and put that slide at the top of the caliper. When I did the left side, the ridged pin was on the bottom. I did look in the bores and did not detect any difference.

Does it really make any difference where this slide pin with ridges is placed? If so, is the bottom the correct location for both rear brakes? 2007 Express 3500 (Roadtrek). 30 minutes of searching the web did not yield an answer,

I don't know about the pins.

Just curious as to why you did not change the rear pads? I put Hawks on the back as well as the front. I only put new disc rotors on the front and kept the original rotors on the back. I think the Hawk pads should give better braking in the back which contributes to improved overall braking. Would be interesting if you did a test: run your current setup for a while and then put Hawk pads on the back to see if there is a difference. It's only $$$

[peteco]

Originally Posted by Roadtreker357

I just cleaned and greased the rear slide pins, nothing appeared damaged. Did not change the OEM pads, but did sand them some to remove glaze.

One tactical error; I did not realize one of the slide pins has ridges along its length, so did not know it came from the top or bottom of the caliper. Only had the right wheel off the ground. Gambled and put that slide at the top of the caliper. When I did the left side, the ridged pin was on the bottom. I did look in the bores and did not detect any difference.

Does it really make any difference where this slide pin with ridges is placed? If so, is the bottom the correct location for both rear brakes? 2007 Express 3500 (Roadtrek). 30 minutes of searching the web did not yield an answer,

Also, how well did the rear pins slide with the new grease compared to old?

[booster]

Originally Posted by peteco

I don't know about the pins.

Just curious as to why you did not change the rear pads? I put Hawks on the back as well as the front. I only put new disc rotors on the front and kept the original rotors on the back. I think the Hawk pads should give better braking in the back which contributes to improved overall braking. Would be interesting if you did a test: run your current setup for a while and then put Hawk pads on the back to see if there is a difference. It's only $$$

I would agree, not a good idea to mix the semi metallics with the ceramics as it will unbalance things and likely reduce stopping power.


The pin thing is interesting, but in reality it probably matters very little as the load is purely circumferential. It may be a leading edge trailing edge thing that might charge squeel or vibration, but I highly doubt it would be a safety thing as long as you have one of each.

[Roadtreker357]

I did not replace the rear pads, mainly because I want to see how the braking is with Hawks just on the front. Still a good bit of rear pad left, too. My thought is to service the brakes again next year and put Hawks on the back at that time. If not happy with braking (whenever we are able to travel again), will go ahead and get the rear Hawks sooner than next year. The end of May we have a trip of about 200 miles to see how the brakes are doing,

Since my previous post, I did see on-line an explanation regarding one pin with ridges and corresponding flat areas. He said the flat is supposed to face the other pin and has something to do with expansion of the caliper. I did not fully understand it. I did notice that the pin with ridges/flats had v-notches cut out of the pin head, whereas the other pin did not. I will use what I have and see if I notice anything that might be related to that pin.

The old OEM black grease was mostly gone (13 years!!!!). I did not really evaluate how well they slide prior to removing. But they did slide. I hope I did not over grease them, so that grease will ooze out and get on the disc.

[booster]

Originally Posted by Roadtreker357

I did not replace the rear pads, mainly because I want to see how the braking is with Hawks just on the front. Still a good bit of rear pad left, too. My thought is to service the brakes again next year and put Hawks on the back at that time. If not happy with braking (whenever we are able to travel again), will go ahead and get the rear Hawks sooner than next year. The end of May we have a trip of about 200 miles to see how the brakes are doing,

Since my previous post, I did see on-line an explanation regarding one pin with ridges and corresponding flat areas. He said the flat is supposed to face the other pin and has something to do with expansion of the caliper. I did not fully understand it. I did notice that the pin with ridges/flats had v-notches cut out of the pin head, whereas the other pin did not. I will use what I have and see if I notice anything that might be related to that pin.

The old OEM black grease was mostly gone (13 years!!!!). I did not really evaluate how well they slide prior to removing. But they did slide. I hope I did not over grease them, so that grease will ooze out and get on the disc.

Yep, the flat, or flats depending on the vehicle, are there to keep the caliper from binding when it gets hot. The caliper will get hotter than the bracket so the holes on caliper will get more further apart than the adapter. The pin having a flat allows a bit of movement.