Speedo bouncing but not working

My VX has been stood for about 6 months. Started it yesterday and the fuel pipe from the fuel filter split so couldn't run it at all. Replaced the pipe today and have noticed that the speedo isn't working when the truck is being driven, however when idling the speedo is bouncing around all over the place and adding mileage on. Anyone got any ideas what is causing this? There was a new sensor fitted on the trans last year that works the speedometer. This was fitted by a mechanic who didn't know what he was replacing and he replaced it instead of the speed sensors on the gearbox which needed replacing and it worked fine then.

I've heard other members with electrical connector problems around the Tranny (knock on wood - I haven't). I would start with climbing under there & checking all electrical connectors you can find. Make sure they are attached securely.

Thanks for that, we've already been underneath to look and everything is connected as should be, also looks really clean.

Wooh thats a good one! I have never even heard of such a thing.
Does your VX vibrate allot at idle? The speed o is electric so unless the VSS is spinning then there should be no reading, particularly at idle?
i wonder if the the needle is not just broken?