View Single Post
  #7  
Old 09-27-2012, 07:17 PM
InTraffic InTraffic is offline
Short Wheel Base
Location: Midwest
 
Join Date: Sep 2012
Posts: 9
Mein Auto: 2012 BMW 750i X-drive
Gentle (and not so gentle!) BMW users,

This is my first post, so if I digress from Bimmerfest etiquette on introductions first, troubleshooting second, I apologize. My symptomology is similar to that stated above, except I am getting the vibration through the steering wheel, the chassis (seat of the pants), and headrest of the unoccupied passenger seat at a glance. This behavior changes with each dealership attempt to correct-- and mind you, every time but the last, they have admitted that it is a significant problem and that BMW is aware it is a problem across the 5, 6, and 7 spectrum. The first set of POS Goodyear LS run-on-flats was replaced as out of specification for unacceptable road force. The dealer has attempted to rehabilitate the brand new Goodyear LS run flats by road force balancing them now a third time. The BMW technical service engineer, in response to a PUMA case (no one has ever described what this acronym stands for) worked with the senior BMW tech at the dealership and the vibration actually got worse then the previous attempt (should have just left well enough alone). I noticed that one of the rear wheels is now on the front and that tire has been described to me as the one with the most road force. It seems that the Goodyear LS run on flats are just POS and they can't divorce themselves from this supplier. They claim there are no alternatives. However, they let slip that another customer just gave up and bought non-runflats and somehow they warranty-claimed the Goodyear POS LS tires.

Anyway, I suspect the run-on-flats, the electroservo assist power steering, and the suspension just highly sensitively telegraph imperfections-- not in the road surface as the BMW dealer describes as "road feel," but minute out-of-round imperfections in the tire and wheel combinations, which appear to have significant manufacturing variation (read: poor quality control) and which are intolerable in this system.

I'd love for this to be a tire-only problem, but I suspect the problem is much more deeply rooted.
Reply With Quote