Da Breaks!

[moribundman]

Sorry about dat.

My right front brake has been wearing the rotor a little uneven for a while. Nothing dramatic, but just enough to annoy me. at over 160k miles, these are the OEM brakes. The piston seals and boots have been replaced a few times during the past 11 years. Last time I changed the piston seals and boots was about 30 k miles ago. Back then I noticed that the guide pins showed slight signs of wear. Because one OEM guide pin costs almost $40 at the dealer, I decided to wait with replacement until I got a chance to pick the guide pins up for 1/3 the cost during a vacation in Germany.

Here are a few pictures that show my passenger side front brake, guide pin and outboard pad. As you can see, the rotor has almost reached its wear limit (slots are wear indicators), the pad is down, too, and both, rotor and pad show lightlly uneven wear.

The lube that I used on the guide pins has failed and has caused a sticky caliper, to which I attribute the uneven wear. Check out the dirty guide pin with lube remnants and the cleaned guide pins, which show wear and probably some corrosion.

Click the images for larger pictures.






Those don't look fly!



PS: Yes Ms Wan, those pads don't have shims.

 

[Shannow]

Yep, grease looks like it's turned to glue.

What do Audi recommend ?

Zinc Oxide ?

 

[moribundman]

Audi uses and recommends ATE high temperature brake grease. I used Plastilube, which is also sanctioned and which is commonly used on guide pins. I have used Plastilube in the past with good success. I'm pretty sure the guide seals on the right front caliper aren't good anymore and let moisture in. I live in a marine environment, remember? The guide pins in the other three calipers didn't have that issue and had okay looking Plastilube in the guides. I'll have to get new seals and new guide pins. I am going to use Permatex Ceramic Extreme as lube this time around.

 

[JHZR2]

ATE powerslot rotors come OE on Audis??!?!??

JMH

 

[moribundman]

Did I say that?

My Audi came from the factory with ATE/TEVES front brakes with solid, vented ATE rotors and ATE pads and with Lucas rear brakes with ATE/TEVES solid discs and ATE pads.

I have been using ATE Powerslot rotors more than 7 years. The Powerslot rotors (now called PremiumOne) are not very expensive at $63 per unit.

 

[mechtech2]

We pretty much have settled on synthetic high temp wheel bearing grease for brake lube needs.
A can lasts forever, even in the shop.
Specialty lubes just don't seem to hold up as well or better.

 

[moribundman]

So I could use the RL CV-2 that I have?

 

[JHZR2]

Originally Posted By: moribundman
Did I say that?

You said "at over 160k miles, these are the OEM brakes".

Do you like them or note any difference compared to standard ATE or Balo rotors? I might be interested in using these sort of rotors for our various applications.

Thanks,

JMH

 

[Pablo]

That looks almost exactly like the f. brake set-up on the 1996 Volvo 850. I followed the Volvo manual and used high temp silicone grease. The pins from last use looked OK, dry but no black crud or wear. 115,000 miles or so.

 

[moribundman]

Originally Posted By: JHZR2
You said "at over 160k miles, these are the OEM brakes".

Common sense suggests that I did not include wear parts. The calipers, caliper mounting brackets, brake hoses and other hardware (master cylinder, booster, reservoir) are the factory-installed parts.



Quote:
Do you like them or note any difference compared to standard ATE or Balo rotors? I might be interested in using these sort of rotors for our various applications.

The elliptically slotted ATE rotors show less signs of brake fade than do the solid ATE rotors. I'm talking about hard driving in the Sierra Nevada with a fully laden car. The slots are also a visual wear indicator for the discs (and essentially the pads, which have only marginally longer life than do the rotors). After all, my Audi doesn't have even a mechanical brake wear indicator, although in some people's minds this is a very complex car, riddles with fragile gadgets and electronics.

I do like the slotted rotors and I am going to be on the third set soon.

 

[cos]

mechtech2,

Quote:
"We pretty much have settled on synthetic high temp wheel bearing grease for brake lube needs."


Thanks for the tip! Any one in particular? I have a tube of Mobil 1 grease.

I have used the Ford recommended dielectic grease and have noticed it doesn't seem to hold up/last long although the brakes on my Fords wear/work well.

 

[Gary Allan]

Quote:
although in some people's minds this is a very complex car, riddles with fragile gadgets and electronics.


I see the error of my ways. You're right. They're just a tick above a VW in wolf's(burg) clothing.

(now for the mandatory rebuttal about what really happens at Wolfsburg in spite of the obvious pun intended)

3 sets in how many miles? Amazing.

 

[Pablo]

Blast from the past:

http://www.wak-tt.com/tt/tt_docs/brakesqueal46-97-01.pdf

I went looking for the composition of Plastilube and saw this Bulletin - Plastilube Moly 3? Now Plastilube has no mention of Mo. So I assume Audi found out it wasn't the ticket.

Your guide pins are 7 mm hex drive, right?

Once I saw how the pins slide in the rubber housings I used Sil-Glyde: http://www.agscompany.com/products/productFiles/1130183947_Brake Lubricant - TDS.pdf I didn't want a petro related grease, synthetic or not in there. I used the Sil-Glyde fairly heavily.

 

[moribundman]

Pablo, there are at least three companies producing "Plastilube." I have been unable to find Plastilube Moly 3 when in Germany last time. Everywhere they kept telling me it was simply Plastilube. I have the ATE, Teroson and Henkel versions. They seem identical, going by looks and smell. BMW sells ATE Plastilube at the dealership for brake jobs. Plastilube has in the past worked fine for me. The guide seal is damaged on the guide pin that has the horrid mess baked on. The other guide pins are all fine, so I think the grease in the one guide/guide pin assembly went bad due to moisture ingress. VW and Audi do not use Plastilube anymore. They have their own high temp grease, which to me feels like a silicone grease. The actual manufacturer is not mentioned on the tube.

I think the guide pins have a 7 mm Gary Allen head.

 

[Pablo]

You did write something that got me a bit worried....water intrusion...I mean I just popped the caps back on...all was clean but I made no extra effort to assure a water tight seal...I think when I put my winter wheels on I'll check the caps, maybe seal them with silicone grease as well....hmm....

Yes Gary Allan head = hex

 

[Gary Allan]

Only those standing tall can make such good targets

 

[Auto-Union]

Hmm, I just use Permatex Nickel anti-sieze.

 

[artificialist]

I have seen plenty of people use permatex anti-seize with great success.

I have also seen people use Coastal High temperture brake caliper grease with great success. It is what I use.

 

[Jim 5]

I usually sand my guide pins gently by hand with very fine sandpaper, then buff them to a mirror polish with a cotton buff and jeweler's compound at every brake job. I haven't had any sticking calipers since I started this procedure. I also obviously have too much time on my hands.

 

[mechtech2]

Anti-seize is not a good lubricant for moving parts. It is often used for brakes because it is on hand and thick. But that's not what it is made for at all. [But you can get lucky with anything.]
Di electric grease is not great, either.
Dedicated silicone brake grease is OK, but I don't find that it lasts any longer than high temp wheel bearing grease on brakes.