Speedometer works intermittantly on 1994 Buick Roadmaster

I recently started having problems with my speedometer. Sometimes it works and sometimes it doesnt. I had it in repair shop at least 3 times. They replaced some sensor in the rear end and the transmission shop checked some sensor in the transmission and said it was fine. I noticed some small greasy wires connected to transmission housing. What do you think causing the problem?

Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
1 answer
inside wear on the output gear. the bullet is new from the sounds of it but the part that drives it may be dished or worn out.

Roy