Hey there USMC3. First off the sensor by your oil filter is your crank-sensor, and is for ignition timing ect. Or do you mean oil sending unit ? There in the same area. The Speedo runs off your tranny, and just because you cleaned it does not make it good
They have been known to go bad. I would check the wire all the way to your Speedo for defects, and reseat the connector that fits into the back of your Speedo, and while you have the connector out check for pushed pins. (not that they magically become pushed). If that don’t do it, then it might be your speed sensor, or your speedo itself. Good luck. . (I’m just a shade-tree mechanic, so don’t take what I say as the gospel )
