I called the dealer today to find out what could cause the speedometer to quit working and he told me that if the magnet on the right front disc gets chewed up to bad from the mud it won't work. It is $65.00 for the new solenoid. That SUCKS! Any one else had this happen?

Never had the sensor chewed up, but have had mud plug the holes in the disk. If the holes get filled, the sensor may not 'see' them as they go by. Otherwise I would make sure the sensor isn't knocked loose or the wire torn. Don't know what else to try.
Farmr

Jeffr, If it helps your feelings any the new speedometer sensor has been improved and has a metal cap over it so that the grit does not chew it up. I replaced mine last year right after the retrofit kit became available. It is very simple to install and seems to be durable.