Mustang 2000 Rear Disk Brake Repairs

[JerryR]

Hello there everyone. I'm hoping someone can help me with a maintenance question.

I'm trying to compress the rear disk brake slave cylinder on my 2000 Mustang GT in order to install new pads. The slave cylinder has a connection on it for the parking brake. However, prior to beginning work, I chocked the wheels and released the parking brake handle completely. Therefore, the parking brake tension should be relaxed.

However, when I try the ole C-clamp trick to compress the slave cylinder, I find that it does not compress far at all and since I don't want to break it, I do not put any real force into it. I am guessing that some component of the parking brake assembly is preventing the slave cylinder from compressing.

So, my question to you is, "does anyone know how to properly relax the parking brake and compress the slave cylinder on the rear disk brake so I can install the new pads (which are thicker than the old pads?).

Again, this is in reference to a 2000 Mustang GT.

Thanks in advance for any help!

[The Deuce]

Shooting straight from the hip here without a manual handy. Please forgive the dumb questions, but have you taken the lid off your resovior? I've never done a brake job that was real hard to compress the cylender, only on my old Maxima you had to screw it back down in the rear.

Check the res, and grab a Chiltons manual and give it a read. Shouldn't really be a trick, even if you have ABS.

[JerryR]

Thanks for the reply.

Well, I don't think it is the fluid level in the reservoir as I can compress the front calipers with no problem whatsoever. I believe it is related solely to the rear parking brake assembly resisting my efforts to compress the cylinder. However, I don't know how to compress it.

One person I talked to suggested (as you did), screwing the caliper back down. However in examining it closely, I found that it is held rigidly in place and it didn't seem like it would rotate - not even with a special tool to fit over the slave cylinder piston and with notches to engage the notches in the face of the piston. So, I'm guessing that's not how it works.

My other suspicion is maybe there is an adjustment within the parking brake that you have to release to eliminate all tension but I don't know what/where it is. This would seem reasonable since it is a ratcheting type of parking brake. But the question remains, how do you release it fully?

Anyway, I realize I probably need to buy a maintenance manual but I don't believe Chilton has put one out for this year model yet and I don't have the money for the Ford one (though I'm sure it is a good one).

Just hoping to run across someone on this forum who has performed this maintenance before.

Thanks for the reply!

[Hammer]

I think the rear brakes should be the same in all 94+ v6 and GT models. So you may be able to look at a Chilton's or Haynes from an earlier model.

Also, here is a good general Mustang brake site:
http://sn95brakes.cjb.net/

[MiracleMax]

That should be 'cause they screw in. The rear brakes don't compress like a regular caliper, or so I've been told by a coupla people

[JerryR]

Ok, thanks for the info. So, I guess I'm going to have to find a "special tool" to turn the brake piston cause I dont have one and it looks very much like it needs one. The piston is circular (surprise?) in shape but has two V shaped notches cut out of opposite sides (horizontally) so that the piston can slide over the protrusions on the backside of the inboard brake pad. So, I guess the tool would fit in those notches and turn the entire piston cylinder. If anyone knows for sure on this, let me know.

Thanks again.

(Kicked another Monte Carlo SS's butt the other day. You'd think they would learn....)

;-)

[Ares]

You can find a universal type tool at Auto Zone or probably any decent auto parts store. It is boxed shaped with 5 sides having different pegs sticking out. Some square some round. The one I bought I had to cut off two round pegs(had 4 on side I needed) so that it would fit the two slots on face of piston.

The piston on rear caliper screws in clockwise.

[Shaggy]

Not that i recomend it or have aver done it :cough: :cough: But it you are REALLY careful you can do it with a pair of channel locks but you risk acidently grabbing the boot and tear it the Lisle tool they are talking about is cheap enough though if you have the few bucks get it instead. if you want to spend "lots" of money you can get this type here

Here is the cube one he is talking about which is more than adequate if you are not doing rear disc brakes all day everyday

[Ares]

Yep one in second link is one I'm talking about $7, cant remember what I paid.

[JerryR]

Ares and Shaggy,

Thanks a bunch guys! I'll look into the el-cheapo cube since that's probably what I need. Thanks especially for the picture - as they say, it's worth a lot of words.... :-)

I just wanted someone (who had done it preferably) to tell me that yes indeed the piston does screw in clockwise. I had various opinions on whether it screws in or there is some other mechanism to adjust it (all from work friends).

Also, when I first took it off to check the pads in the back, I found that the notch on the leading edge of the piston no longer lined up with the stud on the back side of the inboard pad. Not sure what moved as I didn't actuate the brake but since I didn't have the tool you mentioned I just pried on the right hand notch (gently) to realign the notch and pin so I could slide the caliper fully on again. I found using this technique that the piston doesn't rotate very well. Obviously just pushing on one side isn't going to give me the advantage of turning the entire piston uniformly but I was surprised at how tight it was anyway. So, I wanted to ask you guys, is it a very tight fit so that when you have the tool, the piston is still fairly tight to turn (in the clockwise direction)? Just wondering how tight it is.

Also, I have one other question if you can put up with me. I have 32000 miles on my GT now and I'm a fairly gentle driver in terms of braking. However, I figured I was probably getting close to a brake job on the car. Well, when I checked the front disk pads, there was hardly _any_ wear at all. In fact they are only about 1/16" less thick than the new pads I had purchased. However, the rear pads are about 1/2 the thickness of the new rear pads. So, my question is this, realizing that the front pads are probalby semi-metallic whereas the rear ones are just organic, should I expect this type of wear pattern? I had always heard that since the front brakes do most of the stopping, the front brakes should be much more worn than the rear brakes. However, in my case, it appears to be the other way around. Does this wear pattern match your cars' experience or could I possibly have some type of balance problem in the master cylinder? Just wondering. The car stops wicked fast with no sign of brake fade but I was just curious about this. I hate to mess with it if it's working ok.

Hey, this is a GREAT forum and you guys have been super to help me. Many thanks again!

JerryR

[Ares]

Yah piston is not easy to turn even with proper tool.

[JerryR]

Ok,

Thanks for the confirmation Ed. That's good to know. So, once I acquire the proper tool, I have some hope of being able to move it. Guess the gasket and seal are pretty tight around that slave piston.

Thanks a bunch for all the replies.

Also, nice car and web site.

Some day I hope to beef my GT up a bit too but I'm going to wait until the extended warranty runs out! ;-)

Thanks again,

Jerry