Sorry for nagging guys... Recently I had my discs machined since I started getting some vibration braking and they had very little wear. I think I put things back correctly: put the discs and the holding screw, tucked the pads snugly against the discs, placed back callipers and carriers and tightened/torqued everything to spec, including the wheel nuts. Then, before driving, I applied some progressive and gentle pressure to the brakes to bed things in. Problem is, vibration is annoyingly back just a few weeks in and the front discs have a strange wear pattern: the pads made contact in a gradient so to speak, more on the outer edge and less toward the inside and it's obvious they still didn't make full contact closer to the center, as per the picture (you can see some rust under the edge of the pad). Car seems to brake fine thought. I'm scratching my head and wondering if I did something wrong, if the pads (that were reused due to very little wear) had worn in the opposite pattern before machining the discs, or if the discs were not machined correctly and were thicker going for the center to the edge... the rears still have too little wear to tell but they seem to be wearing uniformly (were also machined at the same time and place). I've changed bracket before on other vehicles but this is a first...

 

And why is it vibrating again??? Could the shop that messed up my rims and torqued the lug nuts incorrectly have also affects the wheel hubs? I get so annoyed and obsessive with these things... 👿

Edited 29 June, 20223 yr by pcspinheiro

I meant "I've changed brakes before..." not brackets, stupid autocorrect on my phone...

Edited 29 June, 20223 yr by pcspinheiro

Sorry that I maintain this monologue but hopefully someone will chip in. Just wanted to add that this uneven contact happened on both sides in the front, and I did make sure the pads went in as they were before (inner/outer)

I would fit new disc pads along with the disc rotors as they wear together.

Yeah, maybe the pads had worn more on the inside before I had the discs machined and now they contact more the outside of the discs... I did not think of installing new ones because everything was so unused. In either case, the car brakes fine, but I can again feel the slight judder when braking, which annoys the hell out of me and makes me wonder if something is wrong with the wheel hubs... I do still have the bent rim on the car (working on getting new ones ASAP), but I guess this would not cause the slight judder at low, almost stopping speed.

Your bedding in process might have been too gentle. Try braking hard from about 100kph down to 10kph several times in succession (it is important not to brake to a stop during this process).

 

If this doesn't help, then replace the bent rim before investigating the brakes further.

8 minutes ago, D402 said:

Your bedding in process might have been too gentle. Try braking hard from about 100kph down to 10kph several times in succession (it is important not to brake to a stop during this process).

 

If this doesn't help, then replace the bent rim before investigating the brakes further.

 Cheers for this! True, I'm a serene driver and reach for the brakes sparingly... I should have pushed them harder on the first few trips without stopping (to avoid very hot pads and discs to stay (and cool) in contact, i suppose.

 

A mate of mine who's a car mechanic also told me just now that using the same pads may be to blame. Said they wore in a certain pattern and are now wearing the discs in the opposite way. It's happening exactly the same on both sides of the car, so I'll just try your suggestion of braking harder a few times on my commute.