Steering wheel vibration under moderate braking

[SuffolkD at aol.com]

Vibrations at speed in my 4000S was lower a frame bushings worn out.

Wheel sound like a worn bearing on corners was loose lug bolts once: 200 20V 
Avant

light braking getting shudder / vibration (clunking like) was worn bushings 
in the suspension.

moderate braking getting shudder / vibration

Heavy braking resulting in  MASSIVE wheel shimmy is usually warped rotors or 
brake faded rotors.

Any light braking that grabs then lets go to grab again is a warped rotor.

Drag the brakes at 10 MPH to check.

I took a Chevy Malibu and fadded the brakes in 1 1/2 laps at NHIS, which 
resulted in massive wheel shimmy.  Cooled down the return trip was smooth braking.

Also make sure your guide pins aren't frozen resulting in uneven pad wear.

-Scott by BOSTON