OK so ive added a 1st grade paint drawing of what my brakes are doing...the black is the hub where the lug studs are and the brown is the rusted inside part of my rear brake rotors where the pads arent catching and the gray is the good part of the rotor where the pads are touching....car stops fine has new pads and has been bleed...what could be causing this...i searched to no avail and im no expert in brakes...

 

If the car stops fine don't worry about it.

 

Turn the rotors.

 

would a failing caliper result in this? and i do want to worry about it because i looks like **** having a ring of rust all the way around your back rotors 2" wide

 

are the pads fine?

are they new?

 

yes new pads all the way around....the fronts arent doing this only the rear

 

check the rotors then.

ha i somehow missed that you said that you had new pads in your original post.

the rotors might be worn down which means you have to get them machined, or new ones.

there is a possibility of something being wrong with the caliper but i don't have any idea on how to check those.

 

ya its prob time for new rotors neway but they dont seem worn too bad

 

New blank rotors for the rear are only $20-30 too. Cheap fix.

 

So you can measure rotor's thickness with your eyes and conclude they aren't at discard??

 

^ no just figured they probably need it the car is 20 years old but only has 96k miles on it

 

When I replaced all my rotors I was surprised to find that the vented rear disks were substantially cheaper than the solid ones.
Made no sense but was consistent among several vendors (NAPA, Autozone, etc).
Even Mazdatrix's aftermarket disks show this difference- it's not as much but they're in the $70 range and I wanted cheaper.

Ultimately I scored a set of vented disk rear calipers from the junkyard ($10 apiece), rebuilt them and bought new vented disks from NAPA. IIRC, this worked out to be about the same as buying the solid disks and keeping my old calipers.

Thought it was weird then and still do.

 

Demand is poor for the solids, so the price is higher since they sell fewer.

 

I think I know what you're talking about. Not long ago I put new rotors (NAPA) and pads (Hawk) all the way around on my GXL, and I noticed after replacing the back ones that the swept area of the rotors is like 60% or so.

Seemed curious to me that it would come out that way, but I just wrote it off as their attempt at refining front/rear brake balance. Anyway, the brakes work great now, so I'm over it.

Good luck with it,

rootsgroup

 

^how long did it take for them to start wearing normal

 

Maybe I didn't explain it right, I'll try again...

The clean part of the rotor is the part that the pad contacts. That's all the wider that the pad is. Why the pad isn't made wide enough to rub the full width is beyond me, unless it's just to let the rears not grab quite as hard, maybe an attempt to alter front/rear bias or something.

On my car, I'm not worrying about it. On your car, you can make your own choice.

That's the beauty of car ownership.

rootsgroup