Re: A4 brake problem in the rain

[ti@amb.org (Ti Kan)]

Mark L. Chang writes:
> > In Germany there's a bit of a panic about brake failures on A4s in the
> > rain. There've been numerous complaints about the brakes feeling fine after
> > a long 'wet' drive, but turning out not to work properly. Cause of this is
> > likely a buildup of water or road salt between disc and pad.

Below is the full text response from the Audi world site.

-Ti
96 A4 2.8 quattro
84 5000S 2.1 turbo
80 4000 2.0
-- 
    ///  Ti Kan                Vorsprung durch Technik
   ///   AMB Research Laboratories, Sunnyvale, CA. USA
  ///    ti@amb.org
 //////  http://metalab.unc.edu/tkan/
///

01/29/99

-----------------------------------------
Reduced braking performance as a result of road salt

AUDI AG has recently been informed by drivers of its medium-size model,
the A4, of sporadically reduced braking performance when the brakes are
applied for the first time after the car has been parked, or if the
brakes have not been operated for some time.

Upon examination in the workshop, in every reported instance no defects
were detected. The A4's brakes, which have always achieved a
particularly good rating in tests by trade publications, exhibited
efficient deceleration.

Following initial investigations by Audi's technical experts, whose
findings were confirmed by ADAC experts, it is suspected that new types
of road salt, in particular magnesium chloride used in a technique known
as "wet salting", affects the friction between the brake disc and the
brake pad.

Audi's technicians are working intensively on finding a solution to the
problem as rapidly as possible.  Independently of the outcome, AUDI AG
and motoring associations recommend drivers to follow a well-established
piece of advice for winter driving: traffic permitting, it is advisable
to apply the brakes intermittently, especially before the start of a
journey and before parking the car.  With this simple technique, the
driver can thus make sure that the brakes will function properly the
next time they are needed.
       
AUDI AG, Press: Product and Technology
D-85045 Ingolstadt
Rudolf Schiller (++49)-841-89-32100
Udo Rügheimer (++49)-841-89-37947
telefax (++49)-841-89-32817