Changing brake pads. Where does the copper grease go?

[tuglet]

Hi All

I'm having my first stab at changing brake pads today, as they are squealing like a stuck pig. Car's a Mk1 1.8 MX-5 and I'm changing the front pads only. I've got my new Mazda pads with shims, springs and squealers.

I also have a tub of high temp copper grease which I've been advised will help to stop the squealing, but I'm not sure exactly where to put it. Does it go between the shim and the brake pad when I'm clipping them together? If so, how much do I apply? A thin layer or just a couple of dabs? Or, do I put nothing between the shim and the pad, but rather apply the copper grease just to the back of the shim after it's been clipped to the pad?

Any advise would be much appreciated.

[Gad-Westy]

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

[cs02rm0]

[Gad-Westy]

Ray Luxury-Yacht said:

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

No, you're wrong i'm afraid. How does grease behind a pad stop it from squealing then? The squealing is caused by the rubbing of the pad on the disc, so you must put the grease on the face of the brake pad.

To the op - make sure you put a really big blob on there as it needs to soak into the pad to last 10 or 20 thousand miles. It might help however to smear some on the disc every now and again, especially in winter, as this helps stop the disc corroding, i've found.

Hope this helps.

There was a chap a while ago on Blatchat (Lotus 7 forum) who did exactly that.

[alfa daley]

I do hope the above poster is taking the piss (goes out to smear grease on brakes discs)

Edited by alfa daley on Thursday 11th December 11:14

[wadgebeast]

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

Also worthwhile greasing the caliper pistons before you squeeze them in to get the new pads in too. Will help stop them sticking...

[NiceCupOfTea]

Ray Luxury-Yacht said:

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

No, you're wrong i'm afraid. How does grease behind a pad stop it from squealing then? The squealing is caused by the rubbing of the pad on the disc, so you must put the grease on the face of the brake pad.

To the op - make sure you put a really big blob on there as it needs to soak into the pad to last 10 or 20 thousand miles. It might help however to smear some on the disc every now and again, especially in winter, as this helps stop the disc corroding, i've found.

Hope this helps.

Whilst amusing, fkwitted posting like this is a very bad idea IMHO. Stupid as it may sound, if somebody took your post at face value and did it there could be very nasty consequences for them.

This site is entertainment, but it's also a useful resource. For reference, DO NOT COPPER GREASE THE FACE OF YOUR BRAKE PADS.

[ultegra]

wadgebeast said:

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

Also worthwhile greasing the caliper pistons before you squeeze them in to get the new pads in too. Will help stop them sticking...

BUT NOT WITH COPPER GREASE

YOU NEED TO USE RED RUBBER GREASE ON THE PISTONS

[Mr Gear]

NiceCupOfTea said:

Ray Luxury-Yacht said:

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

No, you're wrong i'm afraid. How does grease behind a pad stop it from squealing then? The squealing is caused by the rubbing of the pad on the disc, so you must put the grease on the face of the brake pad.

To the op - make sure you put a really big blob on there as it needs to soak into the pad to last 10 or 20 thousand miles. It might help however to smear some on the disc every now and again, especially in winter, as this helps stop the disc corroding, i've found.

Hope this helps.

Whilst amusing, fkwitted posting like this is a very bad idea IMHO. Stupid as it may sound, if somebody took your post at face value and did it there could be very nasty consequences for them.

This site is entertainment, but it's also a useful resource. For reference, DO NOT COPPER GREASE THE FACE OF YOUR BRAKE PADS.

Agree. Amusing as it may be to someone well informed, to someone who is actually trying to learn something, your post could be fatal, so don't be a dick please.

[steebo888]

grease on back of the pads.

[TonyHetherington]

steebo888 said:

grease on back of the pads.

Agreed. Not too much is needed, though.

[Ray Luxury-Yacht]

Sorry couldn't help myself. OP deleted.

[Eddh]

I thought it was used for greasing up for finger before you slide it up your arse? Also hides poo stains well.

[The Black Flash]

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

The bit about putting a little grease on the hub is a good tip for alloy wheels, which can react with the steel hubs and stick over time. I've had to loosen the nuts and drive backwards and fowards several times in order to break the seal before now - the grease stops this.

[camgear]

Eddh said:

I thought it was used for greasing up for finger before you slide it up your arse? Also hides poo stains well.

Is that where the term ginger wheelspin comes from?

[ultegra]

The Black Flash said:

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

The bit about putting a little grease on the hub is a good tip for alloy wheels, which can react with the steel hubs and stick over time. I've had to loosen the nuts and drive backwards and fowards several times in order to break the seal before now - the grease stops this.

Remove all the bolts and then karate kick the rim/tyre. Unless you have the kicking power of Stephen Hawking the wheel will come off.

[Gad-Westy]

The Black Flash said:

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

The bit about putting a little grease on the hub is a good tip for alloy wheels, which can react with the steel hubs and stick over time. I've had to loosen the nuts and drive backwards and fowards several times in order to break the seal before now - the grease stops this.

Remove all wheel nuts, drive fast down bumpy road. Job done!


Don't do what I just said

[Mr POD]

No. NO. No.

Modern practice is not to use any grease. It can't cope with extremes of temperature and flows freely during and after brake testing on mountain passes. Copper grease is not viscous enough at high temps. It was okay in the 1960's but will not do in 2008.

Squeal is caused by a variety of things but lets call it 'tolerances'.

Just assemble and make sure everything is nice and clean.

PS

Time spent at Lucas Car Braking Systems working with a Mr Dave Walpole, who started his apprenticeship as a brake development engineer in the late 50's.
He had a tale to tell about alpine testing.

[tuglet]

Okay, so I'm 100% clear here. The grease goes on the BACK of the pad, then the shim clips to the back of the pad so that the thin layer of grease is sandwiched between the back of the pad and the shim. Do I also put a thin layer of grease on the exposed side of the shim where it contacts the piston?

ETA: Bugger. MrPOD posted while I was typing this. More confused now.

Edited by tuglet on Thursday 11th December 11:40

[ultegra]

Gad-Westy said:

The Black Flash said:

Gad-Westy said:

I coat the back of the pad in a thin layer of copper grease. The shim should just stick to it. Be very careful not to get any copper grease on the pad faces themselves. I'd also grease the sliders and put some copper grease on the hub face if you have taken the disc off. If not, put some on the hub face of the disc to aid removal of the wheel in future.

The bit about putting a little grease on the hub is a good tip for alloy wheels, which can react with the steel hubs and stick over time. I've had to loosen the nuts and drive backwards and fowards several times in order to break the seal before now - the grease stops this.

Remove all wheel nuts, drive fast down bumpy road. Job done!


Don't do what I just said

I was once a passenger in a mate's Dyane.

Half way to the pub one night we speared off the road into a ditch.

"Oh good", he said, "The trackrod has come off."

Turned out that he had obtained a replacement trackrod for one that he had bent and when he couldn't free it from the taper fitting on the steering rack he had left the nut completely off and then driven it until vibration had done the rest.

MUPPET.

We extricated the car from the ditch, fitted the replacement trackrod (which was in the boot) and carried on to the boozer.

Edited by ultegra on Thursday 11th December 11:41