I just encountered the same problem with my 02 America today. Speedo was working great until I got into some freezing rain and snow going over the Rockies today. Speedo started to peg out to 80-100-120 when I was only going 60 MPH. Even after I dried out later it still would still do it intermitantly. Here is the rub....If I reach up and touch it while it is pegging out it will immediatly settle down and fix itself. So it is either a grounding issue or a vibration issue. Will isolate it in the next few days and post my results. Gave me flashbacks to the old Lucas...Prince of Darkness days...
