Passenger front brake grinding

[RCsGX]

It started yesterday, there's a grinding noise and once I apply the brakes it gets worse and sounds awful when coming to a stop. I tried doing some fast / firm stops to see if a piston was sticking but that didn't help.

I replaced the rotors and pads last month so the only thing left is the caliper. This morning to rule out a defective rotor I swapped sides and I still get the grinding noise on the passenger front. There's no grooves / scarring on the face of the rotor and the pads look fine. I looked over the caliper and it looked fine too. I was able to compress all 4 pistons so it's not frozen. I checked the dust shield and it's not touching the rotor. I checked the rear rotors and pads to rule them out and they're within spec and look fine.

I ordered a caliper from Sewell but before I install it can anyone think of anything else to check?

**Here's a short clip...

 

[GXO]

Sounds like something outside the brakes is touching the rotor. Have you checked to see if the shims are shifted, or the squealer is bent improperly? Sounds like a simple fix vs. a caliper. If the caliper was the problem you would have pull to a side if one side was stuck (out or in).

I had a caliper fail and it was pulling HARD to one side (stuck in).

 

[RCsGX]

Sounds like something outside the brakes is touching the rotor. Have you checked to see if the shims are shifted, or the squealer is bent improperly? Sounds like a simple fix vs. a caliper. If the caliper was the problem you would have pull to a side if one side was stuck (out or in).

I had a caliper fail and it was pulling HARD to one side (stuck in).

I'm not using OEM pads, I'm using Akebono pads and they came with shims pre-applied so they can't come loose. I checked the little tab against the drivers side and it didn't look bent.

OEM up top / New Akebono on the bottom
http://i140.photobucket.com/albums/r34/rrcompton/Lexus GX470/AkebonoACT976padsVSOEMpads.jpg~original


The only reason I was thinking it was the caliper is because it gets worse when I step on the brake pedal coming to a stop. I had a sticking caliper on my 1st gen Tundra. It didn't pull to the side when I braked but there was a lot of dragging and if I quickly / firmly stepped on the pedal I could free it. The Toyota tech took it for a drive and it stuck on him so I got it replaced under warranty.

I don't have either issue on the GX so I don't know what else to check? It's frustrating because there's only so many parts.

 

[GXO]

I had a bad caliper, so I think, given what you just said, it is probably a good bet.

 

[rz470]

could be related to bearing or half shaft ?

 

[RCsGX]

could be related to bearing or half shaft ?

No it's definitely brake related.

Lets say I'm going 10MPH. It really makes a bad grinding noise when I step on the brake pedal. If I release the brake pedal the sound changes like something is dragging on the brakes but it's not a loud grinding sound. Then if I press the brake pedal again it starts to make the loud / nasty grinding noise again.

I'm going to switch the pads from side to side and see if the noise goes w/ the pads, if not that only leaves the caliper but I would think since it's dragging all of the time that the wheel would be hot and the rotor would be hotter than the other side but when I checked it last night after going for a 30min ride the wheel was barley warm to the touch (same as the drivers side wheel) and I used a digi temp gun and both rotors were about the same temp.

 

[RCsGX]

Here's a pic of the wear indicator. It's on the passenger side / engine side of the caliper:


I copied the same placement as the OEM pad but just to rule everything out should the indicator be at the top or bottom when in the caliper?



I doubt that's the problem because I'm not getting the same noise on the drivers side.

EDIT:

Most threads I've read the indicator is always on the engine side / top so it's fine.

 

[rz470]

If there is no line of the rotors (none damaged) and they look Ok could be the pads if they are ceramic?

 

[rz470]

Since you Already took it a part i would get regular Pads and put that issue to rest .hopefully that fix the problem if not your GX is hunted

 

[RCsGX]

If there is no line of the rotors (none damaged) and they look Ok could be the pads if they are ceramic?

Yeah the indicator isn't scratching the rotor so I think it's fine. When I slide my fingernail across the rotor there are no gauges or grooves what so ever.

I've never had a problem w/ ceramic pads in the past. When my wife took over my Bimmer when I had a Tundra I put new front / rear Stoptech slotted rotors and Akebono Euro pads on there for her. 6yrs later she's still on the same set of rotors & pads.

I did an oil change the other day on her Bimmer and looked at them and they still have plenty of pad left and the rotors looked great too!

Since you Already took it a part i would get regular Pads and put that issue to rest .hopefully that fix the problem if not your GX is hunted

If I replace the caliper and it still makes the noise I'll try some OEM pads. If it still makes the noise I'll try an OEM rotor. If it still makes the noise I'm taking it to Lexus.

 

[rz470]

RCsGX Any news with what's going on in regard to grinding sound?

 

[RCsGX]

RCsGX Any news with what's going on in regard to grinding sound?

I had my wife drive the GX today while I followed along side of her and wouldn't you know it...the front is fine it's the rear that's sticking!!?

I checked the parking brake hoping it was engaged but it wasn't. I looked though the back of the caliper and the rotor still has plenty of meat on it and the pads had meat on them too. I'll tear it down Monday and take a look.

 

[rz470]

So is that mean that parking brake lining is gone ?

 

[rz470]

I think if you turn the sprocket to engage the parking brake more and than drive it than you know if is the parking brake but on the other hand may be better to take it part all the way and make sure everything is in order.good luck and let us know

 

[GXO]

If it is rear it is the parking brake shoes dragging, 99% chance

 

[RCsGX]

If it is rear it is the parking brake shoes dragging, 99% chance

But would the grinding get worse if I applied the brakes?

I've left the parking brake on before (not on the GX since I don't use it) but I've never heard a grinding noise when I applied the brakes and I felt a lot of dragging...I don't feel any dragging.

Can't wait to tear into it to see what the problem is.

 

[rz470]

Don't want to sound crazy but may be your better half used the parking brake and some how your parking brake liner stayed in lock position and some how melted and distorted which caused misalignment which make it sound like grinding although parking Handel is down . And Totally apposite of what is going to my P brake Handel

 

[RCsGX]

Yall think no inside pad would cause a grinding noise!??


There was actually 3 causes for the grinding. The inside upper pad locator and brake pad fell out and separated from the backing plate. The backing plate was wedged in between the rotor and brake dust shield.


The pad was at the bottom of dust shield / behind the rotor.


Because there was no inside pad the caliper piston was pressing against the backside of the rotor...metal to metal grinding.



I ordered new rear rotors and pads yesterday so now I need to either get a new caliper or rebuild it. I'm want to rebuild it but I don't know how to cap off the banjo fitting?? If it was the front I could use a vacuum cap to cap off the line. Anyone have any ideas?


EDIT:
Just checked Sewell and they don't have the pad locators in stock. I have family coming in Wednesday and need my truck. Has anyone used a Napa remanned caliper? I was thinking of buying the one below and rebuild my OEM when I have time.
http://www.napaonline.com/Catalog/CatalogItemDetail.aspx?R=SEBSE3287A_0248611430#

 

[rz470]

This is one of those one in million situation . Even in my racing days abusing brakes so bad that the whole wheel inflame in fire I never seen anything like that happen I want to know what brand those brake pads are ?

 

[RCsGX]

Not sure who made the pads, there are no markings on them?

I couldn't find any local remanned caliper so I had Sewell overnight one to me. They didn't have the pad locators or wear indicators in stock so I ordered a set of Dorman, I only needed the inside top locator anway and the 2 wear indicators.
http://www.amazon.com/gp/product/B001PYJUG0/ref=ox_ya_os_product_refresh_C

I didn't have a wear indicator on my passenger side and in case I don't have one on my drivers side can someone tell me where these go. I know they face the rotor but does it matter if they go on the top or bottom locator and or inside / outside pad???