Brembo front caliper issue?
11-07-2022, 05:38 PM
#1
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Thread Starter
Brembo front caliper issue?
Hello,
Had the brake sensor come on a few days ago and I ordered some ceramic pads to replace the semi-metallic ones that create an absolute ridiculous amount of dust (I think previous owner cheaped out on pads this go around, they were not MB ones). I started with the passenger front wheel and When I removed the pads the inner one was worn significantly more than the outer one. I was able to get the inner side pistons all pushed in with a ractheting caliper spreader. The middle piston on the outer side (where AMG sticker is) moved in and stopped a few mm short of being flush. The other two compressed fine. Threw the pads back in and had my friend pump the brake pedal and that middle piston came out fine and pushed the pad along with the other two. Tried compressing again and same thing, this piston doesnt want to go in as far as the other 5 in the caliper. With it sticking out that far I cannot get the new pads in because I need that few mm of clearance.
Anyone experience this before or have any thoughts? I put it all back together, and wanted to do some research. I didn't want to cause any damage with brute force unless brute force is needed. I want to avoid paying $900+ at the dealer and a indy shop for just replacing pads on 4 corners.
Had the brake sensor come on a few days ago and I ordered some ceramic pads to replace the semi-metallic ones that create an absolute ridiculous amount of dust (I think previous owner cheaped out on pads this go around, they were not MB ones). I started with the passenger front wheel and When I removed the pads the inner one was worn significantly more than the outer one. I was able to get the inner side pistons all pushed in with a ractheting caliper spreader. The middle piston on the outer side (where AMG sticker is) moved in and stopped a few mm short of being flush. The other two compressed fine. Threw the pads back in and had my friend pump the brake pedal and that middle piston came out fine and pushed the pad along with the other two. Tried compressing again and same thing, this piston doesnt want to go in as far as the other 5 in the caliper. With it sticking out that far I cannot get the new pads in because I need that few mm of clearance.
Anyone experience this before or have any thoughts? I put it all back together, and wanted to do some research. I didn't want to cause any damage with brute force unless brute force is needed. I want to avoid paying $900+ at the dealer and a indy shop for just replacing pads on 4 corners.
12-08-2022, 04:38 PM
#3
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'21 AMG53 wDPP & ARC, 19 GLC300 - Former- 10&14 ML BlueTecs, 20 GLE450 E-ABC, 15 Cayenne D, 17 Macan
Are you using a caliper squeezer?
Besides giving you better leverage, they prevent having the piston getting "cocked" in the bore, which can damage things.
Edit: I hope this isn't the case, but the PO may have damaged something in there.
Also (IDK) are the pistons supposed to be "clocked," or oriented in a certain way?
Besides giving you better leverage, they prevent having the piston getting "cocked" in the bore, which can damage things.
Edit: I hope this isn't the case, but the PO may have damaged something in there.
Also (IDK) are the pistons supposed to be "clocked," or oriented in a certain way?
Last edited by mikapen; 12-08-2022 at 04:43 PM.
