Kiwi01

I just bought my first 911, an 85 coupe, 127K miles. The PPI came up with a few issues that the PO took care of, nothing major. Overall the mechanicals were rated in pretty good shape by a well recommended shop. Now that I have the car home I hear a metal on metal rubbing sound that is intermitent ( I am thnking brakes). You cant hear it until the car has been driven for awhile and then only at very slow forward crawl. The sound goes away if you apply the brakes. The sound goes away for a while if you back up and hit the brakes and then go forward. Before I start taking anything apart I was looking for suggestions on what it might be ...

Steve Weiner-Rennsport Systems

Hi:

That sound is normal for these brakes depending on what pads your car has and the degree of rotor wear and surface finish.

Its nothing to be alarmed about unless the brakes are actually dragging. If your rubber brake lines are original at 127K miles, I'd replace them, pronto.

Kiwi01

Thanks for the reply, the PO said he changed the brake lines at the same time he did the brakes about 6k miles ago ... pads and rebuilt calipers. I am checking on any rotor work, the PO was a tinkerer and did the work himself. During the PPI they said the brakes looked good with greater than 50% pad left. I just took another ride ... the sound is more like a metal to metal groan. I had to drive about 6 miles before I heard anything after coming to a stop. If this is "normal", is there anything I can do about it?

Steve Weiner-Rennsport Systems

Let me what brand and model pads you have,...

r911

Did the PO race the car?
When the brakes are first applied (cold) does it feel like they don't grab much? And then when warmed from doing multiple stops, do they seem to work ok?

Check the hoses and see if they look pretty new, and are uniformly hard to squeeze all the way up & down - just to be sure.

You've already changed all the fluids - brake, oil, and tans. oil -- right??

Kiwi01

Searching through the service file I find refernece to:

D569T Google Search ... cant find a name?
D552 RM Google Search gives ... PBR/Axxis Metal Master

Kiwi01

Fluids were changed recently prior to my purchase ...
Swepco 201 in Trans,
Valvoline 20-50 Racing (used for the life of the car)
ATE Super Blue for Brakes

PO's email response when asked about the brakes prior to the sale
" within last 6000 miles brake lines replaced with OEM lines, new master cylinder, pads all calipers rebuilt ... master cylinder was fine just felt like it would complete the job"

The brakes are firm when cold and after they have had a chance to warm up. I cant detect any fade, but I am not an expert. The only issue is the noise.

Steve Weiner-Rennsport Systems

Hi:

With all due respect,....MetalMasters are likely THE WORST pads ever offered to the public.

Their greatest attributes are that make they little dust and they are cheap,.................Thats it.

What they lack is grip (friction) in spades, and they offer poor stopping power from cold to hot compared to many other pads such as Ferodo, Mintex, Pagid, even OEM Textars.

Pople using MetalMasters are always surprised when a decent pad gets installed in their place and then all bedded in. Its a revelation to find that the car will stop well, even when cold.

I would suggest that you get a set of either Mintex Red Box, Ferodo 3410's, or even OEM Textars. Make sure that your rotors are not grooved or are worn close to spec.

I think you'll be a happier fellow,....