Brake pad/rotor installation mistake?

[Pahonix]

I just did my front rotors and brake pads on my 2011 mercedes glk350 this past weekend. Did it at my father's shop in Astoria and then drove home to Portland. Took a look when I got home and noticed that the new rotor wear was different on each rotor. The driver's side is the size and width of the new pads, yay! The passenger side however was only (maybe) 40% touching the rotor. So last night I took off the pads and put them back on flipping the outside to inside. Reinstalled everything, toqued it all down, flushed the brake fluid a little, and it's still doing it.

Is this okay? I'm thinking eventually the pad will be 100% contact like the driver's side.

Driver's side pad


Passenger side pad


No issues driving and no pulling or anything when I press the brakes

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[Pahonix]

Also verified the part numbers were correct from the company I got it from.

 

[arakboss]

@cd90caprice

 

[Phred]

I've done lots of rotors and pads and that is not noRmAl. If you take it apart again mic the thickness of the new pad from the inside to the outside. For some reason it's not square. This type of wear can happen if the anti squeal plate between the pad and piston did not fully register into the piston cavity, and is not allowing the pad to sit square with the piston. If you drive it long enough, the pads will eventually conform to the disc. But something is certainly funky in Rendlesham Forest.

 

[cd90caprice]

Something isn't right. Can you get a pic of the caliper bracket with the pads installed in it? Similar to this angle but with the pads installed.

 

[Pahonix]

I've done lots of rotors and pads and that is not noRmAl. If you take it apart again mic the thickness of the new pad from the inside to the outside. For some reason it's not square. This type of wear can happen if the anti squeal plate between the pad and piston did not fully register into the piston cavity, and is not allowing the pad to sit square with the piston. If you drive it long enough, the pads will eventually conform to the disc. But something is certainly funky in Rendlesham Forest.

So the anti squeel pad was already on the pads. This came as a kit from RockAuto and I bought the cheapest kit ($140). I did this side second and exactly like the other side.

I stopped by les schwab today for their advice, two people looked at it and couldn't offer an explanation.

I compressed the pistons as far as they would go and I believe both are engaging. It got new pad brackets also.

 

[Pahonix]

Something isn't right. Can you get a pic of the caliper bracket with the pads installed in it? Similar to this angle but with the pads installed.

View attachment 861194

Yes, but it might be a day or two.

Also really appreciate everyone taking the time to help, I'm super baffled by this

 

[Ura-Ki]

Caliper hanging up on its slider pins? A piston locked/cocked in it's bore?
Miss machined pad(s)?

@v0lcom13sn0w
Might have some answers here as well!

 

[made in china]

I had that same issue on my truck. The caliper was bad.

 

[v0lcom13sn0w]

could be a number of things. most likely a bad caliper or caliper slides. also could be the pad surface isnt true. could also be a mis machined rotor. would help to see the style of caliper the car uses too


get a strip of sandpaper and a flat surface. put sandpaper on flat surface. take brake pad and sand it by pushing the pad down and across the sand paper. is only part of the brake pad scuffed?

 

[SrMachoSolo]

Besides having a sticking/bad caliper or poorly manufactured parts being the problem, I'd first try to "bed in" the brakes.

Try a few HARD stops and seeing if it pulls then, light/normal stops probably won't show the issues.

-Robert

 

[BBQ Guy]

Bed those brakes down with really hard stops a few times.

Did you clean and lube the sliders?
You'd be amazed at what a good cleaning and lube can do for those.

Did you inspect the area for any leaks, broken seals, misaligned parts etc
What was the wear pattern on the old pads?

Short of that, bad caliper.

 

[Hemlock]

If it's doing the opposite wear on the other side of the rotor I would check the caliper mounting bracket alignment.

 

[Pahonix]

I didn't clean the sliders, I'm probably going to take it apart this weekend and reinspect everything and take more pics.

 

[made in china]

I didn't clean the sliders, I'm probably going to take it apart this weekend and reinspect everything and take more pics.

You can get rebuild kit for the caliper that will include new caliper pin boots, those may be torn or will become torn if you pull the caliper apart to inspect it.

 

[Pahonix]

I'll see if I can find a repair kit locally.

I did just look at it, and the wear line is getting bigger after I hit the brakes a few times

 

[kmk1012]

Besides having a sticking/bad caliper or poorly manufactured parts being the problem, I'd first try to "bed in" the brakes.

Try a few HARD stops and seeing if it pulls then, light/normal stops probably won't show the issues.

-Robert

This here, I normally find a gravel lot and do a few hard stops to cycle the abs system, it vibrates very rapidly and can help seat the pads if that is your problem.

 

[Pahonix]

So just an update. After awhile the wear pattern finally filled out on the rotor and I thought everything was fine. Last Sunday went for a drive and started getting a terrible squeeling sound from that side. I would tap the brakes and it would go away for a second.

I immediately ordered a new caliper, pads, and rotor since I figured those were probably screwed up even though it's only been 6 weeks.

Got the caliper, rotor, and pads installed today and everything seems great. Good contact on the pad and no sounds.

This is the wear on the pads after 6 weeks which was definitely a bad caliper. The right pad is the new pad I installed today and the left pad is the pad I removed today.