Well - it is all my fault at the end -- greedy me...

 

The story is, about 8 month ago I started feeling that brake disks are bended -- pulsation during braking etc... Friend of mine helped me to get 2 used front ones for free, so I've got new pads from pep boys (another mistake of me? :-)) and we've substituted old disks with "new" ones. Driving experience became much better but seem to degrade slowly -- pulsation was comming back... well - not long ago I've got another two rear disks from newer impresa which seem to be thiner a bit but seems to be fine - hopefully caliper goes far enough ;-) So I've installed them, now it seems to have no pulsation at all but the problem which started to appear somewhere in summer (ie a month after I changed front disks):

when braking and almost when stopped, ie speed is 2-3 mph and foot is already releasing brake pedal a bit to don't stop too rapidly, there are 2 things

1. periodic whistling, so it means that some of the disks are not exactly straight

but what is worse

2. there is a sound which is hard to describe: probably it would be similar to 'pads jumping in their craddles', ie it is also periodic, so at every spin like smbd hits the empty can, or metal pad drops back to metal base... Hard to describe

This sounds seems to be absent when driving on cold "pads" -- ie just started driving and didn't brake too much yet

 

I can't figure out what can be the source of the noise... For the experiment I've changed one of the pads -front right, which made most of the noise, with old one I had, which is still fine, at least it didn't make such sound before... First I thought that noise is gone, but it came back...

 

What can it be?

 

Another question for poor non-English native speaker. What each numbered part means?

on this picture (from impreza but seems to be close enough).

I thought that may be part 1 is kinda related to the clicking sound? because when I took old pads out, these things were quite loose seems to me. On autozone I can see things like breake pad/show, also I remember about shims etc... I just don't want to mix up things ;-)

 

Another question: if changing disks, should I pay attn to smth or can go with the cheapest ones I can find (ebay comes to mind)? :-)

 

Thank you in advance

Well - it is all my fault at the end -- greedy me...

 

The story is, about 8 month ago I started feeling that brake disks are bended -- pulsation during braking etc... Friend of mine helped me to get 2 used front ones for free, so I've got new pads from pep boys (another mistake of me? :-)) and we've substituted old disks with "new" ones. Driving experience became much better but seem to degrade slowly -- pulsation was comming back... well - not long ago I've got another two rear disks from newer impresa which seem to be thiner a bit but seems to be fine - hopefully caliper goes far enough ;-) So I've installed them, now it seems to have no pulsation at all but the problem which started to appear somewhere in summer (ie a month after I changed front disks):

when braking and almost when stopped, ie speed is 2-3 mph and foot is already releasing brake pedal a bit to don't stop too rapidly, there are 2 things

1. periodic whistling, so it means that some of the disks are not exactly straight

Your describing brake squeal? It happens sometimes and it's not dangerous, mostly just annoying. Try installing new "anti squeal" shims (2 & 3 on your diagram) underneath the pads. If that doesn't fix it, then I wouldn't continue to worry about it. You can also try anti-squeal compound (permatex, etc.), under the pads, but I haven't had good luck with it.

 

but what is worse

2. there is a sound which is hard to describe: probably it would be similar to 'pads jumping in their craddles', ie it is also periodic, so at every spin like smbd hits the empty can, or metal pad drops back to metal base... Hard to describe

This sounds seems to be absent when driving on cold "pads" -- ie just started driving and didn't brake too much yet

 

I can't figure out what can be the source of the noise... For the experiment I've changed one of the pads -front right, which made most of the noise, with old one I had, which is still fine, at least it didn't make such sound before... First I thought that noise is gone, but it came back...

 

What can it be?

Sounds like you're describing the shifting position of the pads shift fore and aft. After applying the brakes in reverse and hearing a thunk, you can hear the pads shift back to the front (thunk) when applying the brakes in a forward direction. Just a single clunk, not a repeated noise. My Subaru has done this since it's been new, I don't even pay attention to it anymore. Again, nothing serious.

 

Another question for poor non-English native speaker. What each numbered part means?

on this picture (from impreza but seems to be close enough).

I thought that may be part 1 is kinda related to the clicking sound? because when I took old pads out, these things were quite loose seems to me. On autozone I can see things like breake pad/show, also I remember about shims etc... I just don't want to mix up things ;-)

Depending on how much rust has taken over, some of the shims and clips won't fit as tight as they did when it was new. Here in Detroit they throw a ton of salt on the roads in winter. Every car I've kept more than 6 years has had deteriorated brake performance (odd wear and noise) as a direct result of some serious corrosion to critical brake components. I wish auto manufacturers would get off their rump roast regarding this problem.

 

Another question: if changing disks, should I pay attn to smth or can go with the cheapest ones I can find (ebay comes to mind)? :-)

I'm not understanding this last question.

Your describing brake squeal? It happens sometimes and it's not dangerous, mostly just annoying. Try installing new "anti squeal" shims (2 & 3 on your diagram) underneath the pads. If that doesn't fix it, then I wouldn't continue to worry about it. You can also try anti-squeal compound (permatex, etc.), under the pads, but I haven't had good luck with it.

 

Yeap - that is what I did - I always put some compound but couldn't find shims in autozone etc for my car but after a while it stops help

 

Sounds like you're describing the shifting position of the pads shift fore and aft. After applying the brakes in reverse and hearing a thunk, you can hear the pads shift back to the front (thunk) when applying the brakes in a forward direction. Just a single clunk, not a repeated noise. My Subaru has done this since it's been new, I don't even pay attention to it anymore. Again, nothing serious.

It is different though: it makes noise not once, but on every revolution. I doubt that gravity force make pads go back down to get shifted again with next revoltution.... That is why I thought about part 1 which under alternating load from the pad due to slightly bent rotor can shift and make such nasty sound

 

Depending on how much rust has taken over, some of the shims and clips won't fit as tight as they did when it was new. Here in Detroit they throw a ton of salt on the roads in winter.

 

Here it is as bad :-/ but the thing is that part 4 doesnt get rusted if I'm not wrong, so performance deteoration due to rust has mostly to be reflected on the brake rotor quality

 

 

I'm not understanding this last question

Sorry -- my bad English showed up -- the question was: why can't I buy cheap brake rotors? :-) And I've heard some words of wisdom that cheap rotor from autozone + ceramic pads would work nicely if installed properly. so probably I will just go with autozone VALUCRAFT which is believed to be the same as their DURALAST with longer warranty

 

Now the question is just about which pads to use and there is lot of discussion was done and many people say that PBR are nice but I've found

[/url]http://www.jimrothe.com/volvo/pbr_brake_pads.html

and now I'm wondering...

Yeap - that is what I did - I always put some compound but couldn't find shims in autozone etc for my car but after a while it stops help

Same experience here. The goop works for a little while, but makes a mess of things for the long run, then the noise comes back anyway. The pad shims are available from a Subaru dealer.

 

It is different though: it makes noise not once, but on every revolution. I doubt that gravity force make pads go back down to get shifted again with next revoltution.... That is why I thought about part 1 which under alternating load from the pad due to slightly bent rotor can shift and make such nasty sound

Yeah, if it's a warped rotor then you should feel some pulsing in the brake pedal as well.

 

Sorry -- my bad English showed up -- the question was: why can't I buy cheap brake rotors? :-) And I've heard some words of wisdom that cheap rotor from autozone + ceramic pads would work nicely if installed properly. so probably I will just go with autozone VALUCRAFT which is believed to be the same as their DURALAST with longer warranty

 

Now the question is just about which pads to use and there is lot of discussion was done and many people say that PBR are nice but I've found

[/url]http://www.jimrothe.com/volvo/pbr_brake_pads.html

and now I'm wondering...

I can't comment on on any aftermarket parts, I've never used any. I would think that brakes wouldn't be a good place to try to be too thrifty. Cheap parts are made of cheap materials.

 

I've happy with the OEM pads for normal driving. I've heard people say good things about the ceramic pads, but I don't know if they shorten rotor life or not.

Same experience here. The goop works for a little while, but makes a mess of things for the long run, then the noise comes back anyway. The pad shims are available from a Subaru dealer.

I've found some on partsamerica.com for about 23$ set, including the pad clips I'm suspecting in the first place... now I just need to decide if I have that money to spend :-)

 

Cheap parts are made of cheap materials.

well - most of the time it is analogous to the different brands of cars -- they differ in price a lot but they do their function - drive - better or worse but they have to comply with STANDARDs and REQUIREMENTs, otherwise they wouldn't be on the market

 

I've heard people say good things about the ceramic pads, but I don't know if they shorten rotor life or not.

as I've understand ceramic is more gentle with rotors but usually more dusty... I don't care about the dust must :-)