View Single Post
  #30  
Old 07-13-2011, 07:06 PM
Yorgi's Avatar
Yorgi Yorgi is offline
Officially Welcomed to the 'Fest
Location: Toronto
 
Join Date: Mar 2005
Posts: 3,404
Mein Auto: '04 M3 / '06 650i Cab
99.9% of the time "warped" rotors turn out to be brake pad deposits on the rotors. Deposits can form 2 ways:
1) From over cooking the pads (heavy repeated braking). The deposits will look like smudge marks on the rotor that almost look like streaks of burnt grease.
2) From parking the car with very hot pads. If you brake hard (say you live at the bottom of a large hill) then park your car with no chance of cool down. This can transfer a deposit on the rotors in the shape of the pad.

Take a look at your rotors with a flashlight and look for anything other than smooth perfectly bright silver discs. If you see deposits 5 or 6 consecutive stops from 60 mph down to 10 mph followed by a 10 minute cool down drive (no braking) should clean them up.

If you hit some pot holes on your trip this could have damaged a ball joint or other bushing in the suspension which will exaggerate very slight rotor deposits. Basically you feel no vibration before the pot holes because the suspension is tight with no play but then start to notice vibrations due to loose/damaged bushings. Slotted rotors can also cause slight vibrations on their own when you brake heavily. Worn suspension would also amplify the vibrations in this case.
__________________
Straight lines are for fast cars...turns are for fast drivers
'04 M3 - track
'06 650i Cab - daily driver
'02 Highlander - kid hauler
'01 330Ci - winter beater


Last edited by Yorgi; 07-13-2011 at 07:08 PM.
Reply With Quote