Un-Even Break Wear

[drhoward]

Hey I have been searching around lookign for a solution but I can't come up with anything. I replaced the rotors and pads on my 93 about 20,000km's ago.
When I did it last time the rotor on the drivers side was completed worn where as the one on the passenger side was in pretty good shape, I just figured the previous owner had only changed the one the last time she did the breaks.
But now my drivers side is starting to squeal and it feels like the rotor is badly worn again. Any ideas whats causing this? The only good thing is a kept the good rotor from the last swap so it won't cost me all that much to replace but I don't want to be doing this constantly

 

[mnmattie]

drivers side possibilities:

sticking caliper
collasped hose

passenger side possibilities:

clogged line

when was the last time the fluid was flushed?

 

[Willard]

Most likely it's just because the caliper can't move.

Make sure you clean and grease the caliper slide pins and the channels they ride in before you put it back together.

 

[drhoward]

I am thinking the caliper is not releasing completely. Does just greasing them up tend to help, or should I buy a new one?

Its the drivers side by the way

 

[mnmattie]

greasing the caliper means greasing the slide pins that hold the caliper to the bracket. if they are dry then using a disc brake lubricant can see if that's the problem. if not then i'd start looking at the caliper and hose on the driver's side.

-mattie

 

[drhoward]

Oh and I have no idea when the fluid was flushed or cleaned last, I have only had the thing for around 5 months now (I have put over 25,000 km's on it in those 5 months though, lol)

 

[drhoward]

Ok cool, I will give that a shot next time I pull of the caliper (greasing the pins that is), if it is something else, what should I be looking for on the caliper its self?

 

[Willard]

I'm not sure the hose or actual caliper can be the culprit. Since there is only one piston, the caliper is relying solely on being able to slide to get even brake wear. As long as the piston moves in and out, there's nothing really wrong with the caliper.

To put it like this, my calipers are original with 215,000 miles and they still work fine granted I keep everything greased up.

 

[mnmattie]

you can have a sticking caliper yet still have the pistion move (slightly though)

and you can have a hose collapse internally creating a one way check valve. you press the brakes and the fluid flows compressing the caliper but when you let off the hose collaspes and thus creating that one way check valve and having the caliper fail to release.

usually if you have uneven brake pad wear (tapered on one side) then you're got slide pin issues, but with one whole side that's wearing faster than the other i'd suspect something in the hydraulic system itself

-Mattie

 

[drhoward]

you can have a sticking caliper yet still have the pistion move (slightly though)

and you can have a hose collapse internally creating a one way check valve. you press the brakes and the fluid flows compressing the caliper but when you let off the hose collaspes and thus creating that one way check valve and having the caliper fail to release.

usually if you have uneven brake pad wear (tapered on one side) then you're got slide pin issues, but with one whole side that's wearing faster than the other i'd suspect something in the hydraulic system itself

-Mattie

Well it sounds like its one or the other, after I installed the new pads and rotors it seemed like the drivers side was getting hotter than the passenger side. How hard is it to replace break lines? I have to say I have never done it before

 

[mnmattie]

http://www.partsamerica.com/Product...Y&MfrPartNumber=BH380318&PartType=228&PTSet=A

you'll have a banjo bolt on the caliper side and the metal line connecting on the other side.

start by removing the banjo bolt (looks like a normal bolt, but with a hole drilled into it to allow motion of fluid) and the two copper washers. make sure you use the new copper washers that come with the hose as this creates a crush seal for the bolt and hose. then there should be a clip holding the rubber hose and metal line junction to the frame of the X, use pliers to grab onto the clip and give it a good yank. you can now remove the brake hose and metal line junction from the frame. (note to up top, spray the metal line fitting where it goes into the rubber line with PB blaster to help with removal) Now use a flare wrench if you have one for the metal line (if not i've used vice grips with good results) to brake lose the metal line from the rubber line. Sometimes the fitting will twist right off, if that's the case then you'll have to replace the metal line which sounds alot harder than it is. if you don't twist the fitting off then you should have successfully removed the rubber line. installing is the exact opposite then bleed away

if you do twist off that brake line, follow it all the way to where it stops (ABS unit) and remove. measure the line and head to the parts store to grab a chunk of line. size is 3/16" double flare SAE thread and lengths are: 12", 20", 30", 40", 51", 60" and 72". they will come pre-flared with fittings and you just bend it to how you need it. easy as that

-Mattie

 

[Shen2187]

Mine did the same thing, My drivers side rotor had completely worn while the passenger side was still new-ish.

Make sure the pins (and the channel they slide into) are well lubricated. Also, make sure the pins are all of the way in the channel and not just half-way. There should be about 1/4" (6mm) of the pin sticking out on each side. (At least that's how mine was, yours may vary.) I've not had the same problem since, although it's only been about 1200 miles....

Hope this advice is of some assistance to you. Good Luck.