Sammamish

Is severity of vibration related to the road surface? Mine does that. I do have stretch of road on I90 where I can get consistent results. What were your RF numbers?

JARO

mine started vibrating after my brake job where I also replaced the rotors. It happens when I apply pressure to bakes lightly. Getting 20' so will see if it continues and will hae the tech look at the mounting of the rotors.

356driver

I doubt if this could be blamed on wheels or tires. If it happened after the rotors were replaced and you only notice it when you step on the brakes, then it sounds like faulty rotor(s).

It could just be a break-in issue because it takes a short period of time for the pads and the rotors to mate with each other. But if this has persisted for more than a couple hundred miles it is more likely a defective rotor.

The rotor(s) could be slightly out of true or could also have a defect in the steel. It is also possible for brake rotors to develop "hot spots" where severe usage (heat) causes a change in the crystaline structure of a spot on the steel surface. But hot spots are less likely on new brakes unless you went out and abused them immediately after installation.

In any case I would take your car back to the shop that did your brakes. You shouldn't get any vibration through brake usage.

JARO

thanks 356...will have them look at it next week and report. This started just recently after a couple of k on the rotors. I only replaced the front rotors and the tech said that after they put the wheels back on they balancing just is not as it was before blah blah blah...the guy runs a respectable shop that only deals with exotic cars and so he said he will take a look at it when I'm back in the shop to get the new rims. If the vibration persists after the new wheels and tires are mounted then for sure I will want them to re-examine the rotors and maybe I can get a replacement. I ordered the rotors from Suncoast and had my tech install. I'll talk to my dealer as well to see what they are saying

JARO

is it possible to tell if the rotor is defective or has a hot spot by looking at it? this only happens during braking at high speeds 50mph+. looked at the rotors with wheels on and didn't see anything funky. Wonder if there is warranty on those as these suckers are expensive.

356driver

Hot spots on rotors will sometimes be visible as blue discoloration in the steel. But not always. Be sure to check both sides of the rotor. Hot spots on new rotors would only occur if you really used your brakes hard or if there is a metallurgical flaw.

An out-of-true rotor might be able to be detected by jacking up the car, free-spinning the wheel, and listening for uneven rubbing between the rotors and the brake pads. But more likely it is only detectable on a brake machine. This means removing the rotors and turning them on the brake machine. Best take it to your mechanic for that.

reubstarr

A workshop campaign was released 3 weeks ago concerning steering vibration as a concern. It appears when the vehicle is stationary for a period such as a week or 2, the tyres come out of round or flat spot due to the weight of the vehicle. Porsche have asked their workshops to try an old fashioned theory that appears to be working. You run the vehicles with 20 psi in the tyres until tyres are warm i.e for 20km's. Then inflate tyres to 60psi for the same period and deflate the tyres to recomended pressures when back at the workshop and that will sort the situation out. This problem seems to have been common in colder countries where as in the warmer climates like Australia it is very uncommon.
Try this and see how it goes

ltc

20psi
I can't even see the tire holding that air pressure once you make your first turn, given the weight of a Cayenne and the sidewall loading.

Would you happen to have the TSB#?

Then again, nothing surprises me anymore, especially after the pathetic A506 rear seatbelt fix...............

rockitman

The tires are not flat spotting. Is that the best they can come up with ? I mean one morning, no real vibration, the next morning I get it on the same commute. This is my second Cayenne with it...the first was w/steel springs too...What bull****!!! There is a design flaw/defect with the suspension geometry or the variable power steering. No car should be so hyper sensive that requires rare perfect tires and wheels balance wise not to shim.

It's would be an easy cheap fix...come on Porsche !!! LMFAO

LeS+

Never Ending Story> vibration Issue !
My car had 19' w/ Pirellis. Now, it has Michelins, much much better, BUT NOT PERFECT YET, still shimmy at highway speeds 70+. PORSCHE NA, LISTEN , THIS IS THE BEST & THE FASTEST SUV, WHAT'S HAPPENING?
we, the customers, who paid a lot of money for a Cayenne (V6,S, Turbo), do not want anymore vibration.

LeS+

ltc

Please allow me to be blunt:
"THEY'RE NOT LISTENING"
They have your money. End of story.

MadFox

I like Lewis.. Lewis puts thoughtful comments into the forum ---- but, Porsche is listening or some things wouldn't have changed that have. FOBS, PCM software updates, Roof rack (hideous initial.. better new one) etc. But, the most important people at Porsche that should be listening to YOU are the ones at your dealership. I used the dealer for my tires.. they learned by trial and error. My dealer is one of the best in the country based on what I've read in all of these postings. If your dealer sucks.. get a new one.. If you are in an area where there is only one, then you have a decision to make. Deal with them or get rid of the vehicle. If my dealer was horrible, I'd gotten rid of my Cayenne --- no doubt.

Lastly, Get the actual print out of your road force balance.. even Michelins have a higher "standard" for road force.. thus you may have some Michelins that the RF is too high for this SUV. It is the only thing (I tried it all - read my posts) that made a difference. I believe that Michelin will allow up to 30 RF on a tire and not "defect" it on the assembly line at the plant. RF much above 10 will still have vibration on a Cayenne.. insist on tires before you put them on your vehicle that are below 15.. if the RF is above 15 don't accept it. I had this discussion with my dealer and he agreed as I had gone 36K and they could never eliminate it (Continentals and Bridgestones).. only minimize the shimmy.. NOW - ZERO -- no vibration/shimmy.. JUST DO IT.. and remember that good guys like Lewis have every right to be upset.. but it does taint their posts! Porsche wants to make money.. and fixing the Cayenne is important.. but they will do it in their own darn German time!

ltc

Now you will likely be stoned, shunned and perhaps banished from this forum.

alex911s

Been watching the this thread, but I swear I dont have that issue i got 17 on my v6 with conti, then move to 18 turbo wheels , now I got 20's no issue.
BUt again my tires are not the continental summer tires. I got the 17 conti 4x4 M+S, 18 Yokohama geolander HTS g052 now i got michelin diamaris XL YR20.
You guys dont think it's the tires?

MadFox

I know it was a huge risk.... but, I'm a Navy fly-guy from the Reagan era and have risk in my blood. Praising Lewis, buying a first year new Porsche, marriage, kids, stocks, golf --- all risky --- but alas, if I must be stoned (careful you hippies from the '60's) I'd rather it be by Porsche owners -- hopefully their stones are measured in carats and after catching a few big ones, I'll run and get that 911 cab. I want to get!