I have a 2002 Silverado 2500 4 X 4.  Today, it got stuck in 4 wd.  It is
the push button type to engage/disengage 4 wd.  The "Service 4 Wheel
Drive" light came on, the ABS light and the "Brake" light also came on and
the speedometer is not working.  I can't get it out of 4 wd.  I tried
putting it in 4 low, and backing up to try and get it out?  Any ideas what
the problem could be and if it is serious/expensive to fix?  Of course, the
warranty ran out 4 months ago!   Thanks