giddyupp

I recently bought new Hawk pads and Zimmerman Cross Drilled rotors from Roger. (As always - great service - thanks). Fronts only - for now.

Just got round to installing them last weekend. I believe I have bedded them in correctly and yet I seem to have two issues.

1. I am seeing a LOT of brake dust on the drivers side wheel only. Passenger side is almost clean.

2. I am also getting some squeaking at low speed.

When I installed the new pads, I also installed stainless steel braided lines. I did also install the shims and bled the whole system. When breaking I am not noticing any pulling to one side or any binding. Does anyone have any ideas. My first thought was that the caliper is sticking but it seems like I would feel some pull when I applied the brakes. Any thoughts would be much appreciated

Cheers

Speedtoys

Which Hawks...HPS or HP+?

If plus..ya..they dust like hell, squeal like a pig, and will eat your cheesed rotors in one set of pads, and if youre lucky, leave a 'vinyl record' like pattern of accelerated wear in rings between the holes.


PS: Always glad to see more SF Bay Area 928s!!

Mrmerlin

get an IR gun drive the car for a few miles without using the brakes then stop the car and check the front rotors for temps with the gun,
if the the dusty side is hotter then you have a dragging caliper AND / OR you have air in the other side

giddyupp

Wow - thats some quick responses. Thanks guy's

The pads are the High Performance Ceramic's. I have an IR gun and will give it a go. If the caliper is sticking, I assume that means a rebuild - right ? If so, is that an easy job?

Bertrand Daoust

Not really a big job.
Remove the calipers.
Take the pistons out 1 by 1 with some air pressure.
Change the dust boot and seal. Change the pistons if they show some wear.
Put some caliper grease on the pistons and seals.
Put them back on.
Bleed the system and voilà.

Here's a good thread on rebuilding calipers:

https://rennlist.com/forums/928-foru...not-to-do.html

Thanks Rob.

ROG100

Hawk Street Pads are the best I know for low dust and low noise. Try Mintex, Textar or Pagid and you will know what I mean.
Have them on my cars and no dust and no noise - how would I know as I am nearly deaf.
Never had any wear issues on the cast holed or X drilled rotors. I do not track my cars just drive fast.

Sometimes the plates inside the calipers can warp and cause a vibration/squeal.

dprantl

When you put in the pads, did you have to force the pads in or did they just slide right in to the caliper? They are supposed to slide in using just your hands with almost no resistance.

These Porsche/Brembo calipers have a design flaw where brake dust accumulates under the pad spacers/guides. Over time, the dust pushes up the guides and it becomes difficult to remove/install pads. I have seen many brakes where an "expert shop" has hammered the pads in on one side. This makes the brakes on one side do much more work than the other because on one side the pads are wedged into the caliper.

I find that Metal Master semi-metallic pads dust the least amount. I am trying out a set of Metal Master ceramic pads right now, they seem to perform better than the semi-metallics and dust the same.

Dan
'91 928GT S/C 475hp/460lb.ft

giddyupp

Pads just slipped right in - no force used at all. I just don't understand why the drivers side wheel is very dirty and the passenger side is practically clean as a whistle.

blown 87

Something is up, they should be the same of both sides.

Tony

I dont care about the dust, my rims are so easy to clean but Im about to torch my car becasue of the squealing...really starting to drive my nuts

what are the quietest pads you can put on a set of X drilled rotors?

And....why dont the backs squeal at all?

blown 87

Did you clean and lube all the metal to metal contact points at the pad to caliper with the right lube?
Was everything absolutely clean when you put it together?
Are you using the factory dampners?
Did you use new factory pads and rotors?
There are a lot of things that need to be done to end up with squeal free brakes.

You can make almost any pad/rotor combo be squeal free, at least for a while, but you can not just throw parts together and hope it works, that will rarely turn out well.

I have cast hole Zimmermans and Mintex pads on mine and they have never made a peep.

tveltman

Do you have a 33 bar rear bias? If not your fronts are doing most of the braking, so they make the most dust and are most prone to squeal, methinks.

SteveG

I posed a related question about protecting rims from dust on the wheels forum. A vendor said "ceramic" pads were the answer. Apparently not. Or is it possible you have one ceramic and one not?

Bertrand Daoust

Maybe a stupid question but are you sure you have the same pads on both side?
Never know!

giddyupp

Drove the car home last night and tested both discs with an IR sensor. Looks like the drivers side was showing about 10 degrees hotter than the passenger side. Soooooo - What does this mean. I am assuming it means that the caliper is indeed sticking slightly - Any thoughts ? - If it is sticking does this mean I should do a rebuild or can it be cleaned ?