1989 Mustang speedometer

Just bought the car. speedometer and mileage do not work. What do i check first?

See if this has a simple cable on the back of the speedo . . . follow it from trans to speedo, take it off and lubricate it. If you have a salvage yard close by . . . look around for a used speedo with the cable for this era Mustang. Good luck! Rocketman

It is most like going to be the speedometer cable or the speedometer driven gear in the transmission. If you raise the car; put it on jack stands; disconnect the speedometer housing nut; and pull the inner cable out you will probably find it broken. If it is you may have to disconnect the cable housing at the speedometer head and pull the rest out of that end. If the cable is broken check the freedom on the input drive of the head as a sticky input drive can cause the cable to snap. If the cable is intact, check that the driven gear in the transmission is turning when the rear wheel is rotated. If nothing has been found so far you will have to check the fit of the square end of the cable into the driven gear and the head input drive. It may have rounded off allowing the cable to slip. Otherwise you may have to take the car to a speedometer shop and they can overhaul and recalibrate the head.

When you put the inner cable back into the housing grease it will speedometer cable grease.

Good luck. Hope that helps.