The 1991 Ford Ranger came with either a manual or an automatic transmission. The truck was offered with your choice of a 2.3L 4-cylinder, a 3.0L 6-cylinder or a 4.0L 6-cylinder engine in 1991. The procedure for changing the lock cylinder for any of these engine or transmission combinations is identical, with the exception of minor mechanical parts attached to the column shifter that are not present on the stick shift version.
Separate and remove the plastic collar around the steering column using a Phillips head screwdriver.
Locate and remove the electrical wiring connector at the back of the ignition lock cylinder, opposite the end you put the key into.
Remove the three fastener bolts that hold the lock cylinder in place with a 3/8- or 1/4-inch drive ratchet and socket. Remove the old lock cylinder from the steering column completely. The 1/4-inch ratchet is smaller and will allow easier access to the steering column. Use the 3/8-inch ratchet for more leverage if the bolts prove too hard to remove with a 1/4-inch ratchet.
Use pliers to separate any mechanical link to the shift lever if applicable on your model. The link rod is shaped like a long C, with 90-degree bends at each end. Pull the link rod off the cylinder, toward the center of the steering column. Pull the link rod off the shift lever by pulling it straight up. Both links are easily removed with minimal force.
Install the new lock cylinder into place on the steering column by hand. Tighten the mounting bolts down between 15 and 20 foot-pounds of torque using a 1/4-inch drive ratchet. Do not over tighten the bolts--doing so can damage the new lock cylinder or strip the threads in the steering column mounting holes.
Reinstall the link rod onto the back of the new cylinder by pushing it in with a pair of pliers. It will simply snap into place. Swivel the link rod up and reinstall it into the shift lever by pushing straight down until it snaps into place, using pliers. Do not use excess force on either end of the link rod--doing so can damage the new lock cylinder and your shift lever.
Turn the truck on and off at least three times while simultaneously testing the steering wheel lock and the shift lever lock. If the steering wheel will not turn, double check the alignment of the lock cylinder and make sure it is mounted correctly. The lock cylinder should be positioned so that the steering wheel locking tab is facing toward the dashboard. When you turn the key, this tab retracts into the cylinder and allows the steering wheel to turn freely.
Reinstall the plastic collar around the steering column with a Phillips head screwdriver, only after you have verified that the new ignition cylinder is mounted correctly and the steering wheel turns. Tighten the screws to between 5 and 10 foot-pounds so as not to break the plastic collar or strip the screw holes.
