Hi all! my 1987 560sl speedometer stopped working a few weeks ago (the odometer has not worked since I have had it-4 years) is this a possible broken gear in the actual speedometer mechanism? are theese electronic (no cable), I read a thread somewhere that mentioned a problem in the transmission. What is the most common problem with these. Any help would be greatly appreciated, I am using my Tom-Tom for a speedometer

Thanks in advance,

-DDAYMEN