sapkan

I was racing a Cayenne S on the motorway the other day and I had to do a few of stops from 250 to about 100 km/h because of slower traffic. Not the emergency jump on the pedal type but steady and progressive. On the last one I noticed as the car was slowing down there was a resonating sound that increased as the car decelerated. It was coming from the front and happened twice after that on gentler stops. Half an hour later I braked from 100 to standstill and it was gone. Could the brake disks have warped or could that be temporary because of the extreme heat generated at those stops? I have done 50 000km and have always been careful not to wash the car when the brakes are hot. I still haven't changed the factory front brake pads. Idrive shows 16 000 km still to go!!

p.s. This is the longest I've seen a car this fast and driven properly do on a set of front pads. I had changed 4 sets of fronts by 40 000km in my WRX ?! I have changed the rears once on the 535d due to heavy DSC activity.

BMW#7

I had a set of warped front discs replaced on my E39 525i. Although I wasn't sure what had caused it.
Also discovered the problem because of vibration during braking.

ipp

Who won?

fünf dreißig

Probably just that the Chamfered edges on the pads have worn down causing it to bounce some. I had 7k miles left on the front of mine, and changed them all the way around this past Saturday. I notice quite a difference in braking.

sapkan

I hope you are right. Will be bored if I have to change disks after all I've done zero track driving.

p.s. whipped the Cayenne off course. easily pulling 4-5 car lengths from 160 to 240 but it was pretty impressive for a SUV. In some of the corners I thought the thing was going to fall over. hihi

daven

Cayenne S is only a volkswagen with tacky badges!

merklebob

check the torque on the lug nuts. you need to use a torque wrench and make sure they are all the same. having one off by 10 lb will warp the rotors esp when you braking as you stated. the torque snubs used by tire shops are not close enough.

sapkan

do you know what torque they need to be tightened to?

simba

What's your WRX and 535d comparision since you've got both?
In my 530i Msport manual, it mentions using 120Nm torque.

sapkan

Thanx Simba. As for the 535d/WRX its a no contest really. My Scooby was tuned to 280ps but still I feel the 535 is superior in-gear. It also handles a lot better and is more stable in faster corners. The scooby has acceleration advantage from start when doing a full bore clutch side-step start and in tighter corners where the torque of the 535 overwhelms the rears and DSC kicks in.


p.s. btw dsc is to aggrresive needs to be toned down. A 535d with a LSD would be an interesting one. BMW are you reading this...