In a message dated 2/7/2013 12:23:53 P.M. Eastern Standard Time,
mcneely4@COX.NET writes:

My  mirror problem is not that the mirrors droop.  My mirrors are
motorized.  They respond poorly, though they do respond.  That is,  press the
switch, and the mirror may or may not respond quickly.  When it  does, it may
jerk, stop, jerk again.  I can get them set as I want, but  it they are not
smooth.  I have never looked into either the mirror  assembly or the switch, but
I figure something is corroded.

Anyone with  experience fixing this who can offer advice would be thanked
for doing  so.

that's how they worked when they were new...