Brake Pad - Greese on Caliper Question

[scottca]

Hi All,

its time to replace my rear pads, have done them before but only ever put some copper grease on the back of the pad to stop it squeeling.

Ive noticed that one side is wearing more than the other so my inital though is that the caliper maybe a little sticky (I dont feel any affects of this when driving etc). Ive never greased the caliper etc when changing the pads.

should I stick some copper grease on them, if so, where is the correct place to apply it, is it on the pin/slider? can I pretty much apply it to anywhere other than obviously the front of the bad and the piston?

do I need to use any specific greese (or can someone recomend some and ill go buy it) ?

Thanks in advance, sorry its a really simple question im sure but im keen to learn and not pay the garages everytime I need something simple doing!

Thanks,

Craig

 

[8bit]

I changed mine recently, the only place I put copper grease was on the little metal plates on the caliper carriers, you'll see them once you get the old pads out. I just got mine off the shelf in Halfords. Don't apply it to the back of the pads, they have an adhesive coating on them to hold them on to the piston and carrier.

When you get the caliper off look at the carrier at the bits where the bolts that go through the caliper go into. You'll see that they have little rubber boots on them, they're called the guide pins. You should be able to push these into and out of the carrier fairly easily. If not then that might be why it's sticking on one side.

If either of the guide pins are stuck then the caliper won't be able to pull the outside pad on that side of the car against the disc. The guide pins can be pulled free of the carrier but you'll need to take the carrier off the hub assembly (I had to anyway as I couldn't get the discs off without taking the carriers off, I've got an LCR with large-ish rear discs). Once the carrier is off, get a pair of molegrips, vise-grips or if really stuck a pair of stub-nose pliers, get a good grip on the head of the guide pin where the caliper bolts screw into and pull them free. Be careful not to damage the rubber boot.

Once that's out, give the pin a good blast with brake cleaner and/or degreaser and a wipe with an old cloth. Scrub it with a wire brush, some more degreaser and let it dry. Give a good blast of degreaser inside the hole it came out of too. If you can, get a thin, round wire brush and have a good scrub inside the hole, some more degreaser then leave it to dry for a few minutes. Grease up the pin with some copper grease, slide it back into the carrier, then push a little harder and it should then slide inside the rubber boot.

Wish I'd taken photos when I was doing mine recently! It should all seem straightforward enough once you get in about it. When you're reattaching the carrier to the hub, the bolts should be torqued to 65Nm. When reattaching the caliper to the carrier, use the new bolts that come with the pads (assuming you get Pagid pads, no need for anything fancy at the rear), don't reuse the old ones. Do those up to 35Nm, I couldn't get the torque wrench over the lower bolts on mine though so had to sort of judge it.

 

[scottca]

Thanks 8bit.

Im a little confused now its gone into the "hub assembly"

so once I get the caliper off, if it moves freely then I wont need to take the carrier off the assembly? if its a slightly rough movement, can I slide it open and grease it in place?

when you say Hub assembly, im not sure what you mean - is that the bit that holds the rear pad (or am I now getting very confused)

Thanks,

Craig

 

[scottca]

I know its not for a mk1, but I think I now know what you mean:

http://www.seatcupra.net/forums/showthread.php?t=225698

looking at that post, post 4 shows the guide pins?

can I grease them inplace if they move (pull them out, grease and push back?)

 

[8bit]

I was just about to post a link to that very thread Yeah that's the guide I used and that pic shows the guide pins, you should be able to push it outwards towards you as you look at the face of the disc.

What car have you got? If it's an LCR then chances are you'll need to take the carrier off to remove the old disc (if you're doing that). If you don't have to then you'll be able to check whether the guide pins move in and out OK. If they do then just clean everything up a bit, grease the metal shims on the carrier a little bit, fit new pads and put it all back together. Torque for the caliper bolts is 35Nm but as I said you might not be able to get the wrench on the lower one.

You might be able to get the pins out without removing the carrier but I couldn't. I had to take the carrier off (it's not hard, just two bolts round the back), get vise-grips on the head of the guide pin then hold the carrier on the ground with my foot and pull hard on the vise-grips to free the pin. With the carrier still on the car you'll be pushing away from you into the wheel arch.

Make sure you've got a can of plusgas too, give each bolt a good blast with this before trying to remove them.