I have another very interesting project that I am using as a proof of concept.
For anyone with a Jeep JK/JKU, the rear brakes have small anti-rattle clips that fit into the abutments on the caliper brackets. For most "standard" Jeeps I have not really seen too awfully many issues, just a few where these clips see to have an expedited wear rate. HOWEVER, for those running big brakes with the rear caliper brackets that move the caliper mounting outboard, I have noticed an increased rate in which these need attention. From my experience it is something that most owners just seem to live with and tolerate when the wear gets to the point that the clips are worn enough or compressed enough that the calipers start making a slight rattle or clunking noise. The noise is almost always only detectable at very low speeds as the friction causes the caliper to rise slightly and then fall back down on the brake caliper abutment. At faster speeds the caliper must "load" itself against the upper abutment point thus causing the caliper to stay in one place.
During this low-speed clunk or rattle, just ever so slightly breathing on the brake pedal instantly causes the noise to stop as it causes the caliper to grab just enough that it loads up against the upper abutment point on the caliper bracket. I have noticed on my Jeep JKUR with the Teraflex Big Brake kit that I seem to go through anti-rattle clips at an accelerated rate, like nearly every 5k-7k miles I'm tearing the calipers off and replacing the anti-rattle clips. I have tried several aftermarket brands and even the Mopar OEM ones to no avail.
Last year during mine and the wife's last season trip to the San Rafael Swell, on about the second or third last day I noticed this ever so slight rattle sound that would instantly stop with a very slight application of the brake pedal. I mentioned to the wife that it was those dang anti-rattle clips again even though she could not hear the noise.

On the last day we happened to be driving through a very sandy wash with a tall ledge on the wife's side and she was able to hear the noise. Upon returning home, I pulled the brakes apart, again, and replaced the anti-rattle clips. No issues the last of the year, even on the couple of local off-road day trips that the wife and I went on.
Fast forward to this season and they've been quiet, up until the last day of our central Idaho trip a few weeks ago when the noise returned and again, instantly quit with a very slight application of the brakes.
I have been racking my brain trying to come up with a permanent solution as this is getting ridiculous. After reading a lot of Jeep forums I have also found that others have experienced similar issues but no permanent solution other than people replacing the anti-rattle clips at an alarming rate.
I decided to tear my rear brakes apart and do some in-depth measuring and try to come up with a plan.
Dial indicator with stem adapter in order to accurately measure movement.
DTI zero'd out with the brake pads pushed all the way towards one abutment.
Then pulled the opposite direction to reveal more than .032" of travel. Well hell, that's enough to make a rattling or clunking noise at low speed. Even before pulling the caliper brackets off the rear end, I grabbed the pads and shifted them up and down and was able to easily get a resulting noise as metal on metal from the ears on the brake pads.
I measured the distance in the brake caliper bracket to see if it had worn, although it didn't look like it was showing signs of wear. I measured both caliper brackets and even dug out my old OEM brackets to ensure there were no discrepancies, and they were all within +/- .003" of each other. I even called a friend who recently was putting a new rear end under his JKU and had purchased all brand new brake components and his brand new OEM caliper brackets measured the same as mine.
So then last week I went to my local NAPA store where I could measure several sets of brake pads and look to see if there was maybe some discrepancies between manufacturers. It was a long shot, but things happen and I've been running the same NAPA Ultra-Premiums for the last while.
The NAPA store didn't have their Ultra Premium, but they had their SG (Severe Grade) so I measured them. I then measured a set of Brembo and Akebono they had on the shelf and all were within +/- .004". It was worth a try, but it appears the pads aren't the issue. In my head I keep thinking it has more to do with the larger rotors requiring the calipers to be further outboard and therefore putting more leverage and stresses on the abutments which in turn result in excessive clearance much sooner than a Jeep with factory brakes installed.
With not really any findings that jumped out at me, I thought I would try to add a little material to my brake pads and tighten up the gap right from the beginning so maybe they wouldn't move as much and create this excessive clearance. It's a thought and one I thought I'd test out.
Wet rag wrapped around brake pad to prevent overheating and a little weld added to one ear of each pad.
I had run several calculations/measurements and decided I would try to shoot for somewhere around .010" clearance as a beginning point. Hopefully that will be the beginning AND ending point.
After adding some weld to one ear of each pad, I kept sneaking up on the overall dimension until I felt comfortable with enough clearance to where the shoe would move in the abutments, but not so much as to have "slop".
With my old pads I used them as the test bed and then added some welds to the new Akebono pads and took them to size.
With the newly sized pads in the brake caliper bracket and DTI zero'd out pulled in one direction as hard as I could.
I then pushed hard the other direction and saw that it netted me a good .009"-.010" of overall clearance. Much, much less than the >.032" I began with.
Now it was time to reassemble everything and give begin testing.
With everything back together and some test miles on it over the weekend so far it is fine. But the real test will be over time. My notes kept for the next time I need to replace brake pads so I don't have to go through this again.
Thanks for looking.