mtnrat

Installed new front brake rotors, pads, and sensors on my 2006 Turbo S 5000km ago. I Used Porsche parts from the dealer (new parts). When I put them on i noticed a slight vibration during braking only at middle speeds. Not when going fast or when going slow. Figured I just had to drive it for a bit. Well long story short my wife drove it out to Powell River, about an 1100 km run. I got there by a different route and drove home. I noticed the vibration had gotten worse, but was not bad. During the way home the vibration became more pronounced. When I got home I took the rotors off to make sure I had cleaned the mating surfaces. Yup, perfect. Put them back on vibration still there. Did a number of panic stops from 65 mph and the vibration got worse. I still had the old rotors so decided to put them back on. I changed out the right hand side first and took it for a drive. PERFECTLY SMOOTH. I just called the dealer I got the parts from. He asked a couple of questions as in did I do the work myself. Which of course I had. Said he would see what he could do and get back to me.
Now waiting for the call back. The pain is that they are the closest to me and 180 miles away.
I found it strange that a new Turbo S rotor from porsche warped.

Andy E.

I find it very odd that a Porsche dealer would sell used parts. I'm pretty sure that Porsche Canada would not approve of this.

mtnrat

I edited the post. I used parts from the porsche dealer in Calgary. They were new.

deilenberger

Any indication where the rotors were made? Some companies with very nice German names are getting rotors made in China. NTTAWT, but I suspect QC may not be quite as high as from a euro factory.

J'sWorld

I bought 16 Porsche exhaust valves from a big name board sponsor and they were so bad I had to send them back. At first I thought they were fakes. The margians and seats were all uneven and not cocentric. Where the heads were friction welded on the stems they were UGLY. Nothing like other P valves we looked at for comparison.

I wouldnt be suprised if they wanted to throw a dial indicator on your hubs to check the runout. On your dime of course.

TomF

Sorry to hear about your issues. Did you bed your pads in properly? Warped rotors are a myth- rotor vibration can often be caused by pad material adhering to the rotors. This happens if the new rotors/ pads aren't bedded in correctly. There are other causes too, but that's the general idea. Search Rennlist for the "Myth of the warped brake rotor."

Cheers,
TomF

MaxLTV

Exactly. It's probably not warped. If the issue happens when brakes are applied, it's most likely uneven pad deposit issue, which should resolve by itself after few days. If the issue is happening when not applying brakes at all, just cruising at steady speed, most likely the rotor is unbalanced or not properly centered, which should be warrantied.

mtnrat

So rotors don't warp. I did bed them in. Strange thing is if it is pad material I would think that both rotors would have pad material if that is the case. I only put my old rotor on the passenger side. The drivers side is still the new rotor. I didn't change the drives side as the vibration had disappeared.

mtnrat

BTW, the dealer wants me to buy a new rotor, give them the old rotor, then they will have their gurus check it and then decide whether to reimburse me.

prosled8

How kind of them...

mtnrat

That's exactly what I thought.
I have the feeling it won't go well.

MaxLTV

so does it vibrate when you press the brake pedal or all the time at certain speed, like an unbalanced wheel would? If the latter, they sold you a defective part, so you should insist on a replacement. If the former, it can be either way (defect or pad deposits) but even then what the dealer says makes no sense to me. Let's say they find out the rotor is fine, and it's just deposits, you would end up with 3 rotors then. I'd insist on a replacement right away or get them to agree that if the issue does not resolve in 2 weeks, they will replace it.

ScootCherHienie

Uh, rotors DO warp, no other explanation for zero run-out when new and easily measurable run-out when measured after experiencing vibration while applying brakes. Rotors can warp after a long (2 hours or more) at speed (60mph or faster) if anything in the braking system prevents minimizing pressure on the pads while driving. Rotors can also warp after a high-speed stop if you keep your foot hard on the brake pedal (causes uneven cooling of the rotor). Interestingly, "warped rotors" can go away by themselves after some driving. Had numerous rotors replaces under warranty (BMW) due to measrable warping and each replacement produces smooth vibration-free stops. Did not stop until dealer finally replaced calipers at my urging... factory calipers were not releasing enough pressure on the brake pads causing drag on the rotor at highway speeds making rotors get VERY hot and prone to warping.

TomF

Uh... Okay, I'll bite.

There is indeed another, (proven) explanation for the behavior of rotor vibration. Read MaxLTV's post above, then read the article I referenced.

Cheers,
TomF

AGARubberDuck

Try stop and go traffic for an hour.. then when traffic seems to clear and everyone is going 70, panic stop moving into a shoulder full of water. Then tell me rotors warping is a myth :P

I get where you're coming from with deposits creating an uneven braking surface from the way pads are produced these days (adhesion vs friction) but that certainly doesn't preclude the possibility of rotors warping.

OP, sure seems like a warranty issue to me. Turbo S rotors are pretty expensive - probably why the dealer is trying to make you front the cost.