Rekey a 1973‐1991 Chevy Truck Ignition Cylinder Lock

There are several reasons why you would want to re-key the ignition lock. Maybe the truck has changed hands and you want more security. For this just remove the old lock assembly and install a new one with a different key. But what if the key was broken off in the lock, someone damaged the lock, the lock is worn-out and it needs to be replaced. In any case a new lock has been purchased which came with a different key and you want to re-key it to match your old key. Not a problem.

Steps

  1. Remove the steering wheel and turn signal assembly. To re-key the lock cylinder you must remove the assembly from the steering column.  If it is a tilt steering wheel it will be much more difficult to work on as it requires a special tool to remove and install the horn ring and retainer clip, but there is a way around it.  Whether it is a standard or tilt wheel, the steering wheel needs to come off. 
    • First, and a must, disconnect the vehicle horn or battery then remove the center horn pad, then unscrew the locking nut until it is flush with the center shaft.  Mark the shaft and steering wheel with a marker or paint to help align the two when reinstalling. 
    • Using a steering wheel puller, gently tighten the puller until the steering wheel pops loose.  If you don’t have a steering wheel puller then a brass hammer will do the job.  Again with the nut flush with the center shaft apply upward pressure to the steering wheel and tap gently on the nut/center shaft with a brass hammer.  This may be accomplished by placing your knees under the steering wheel and flexing upward or by having someone else hold the steering wheel with their hands and pull upward.  After several taps with the hammer the steering wheel should pop off. 
    • Remove the nut and the wheel.  There will be a retainer holding the horn ring in place, remove the retainer and lift the ring out.  Next remove the three screws holding the turn signal assembly to the column as well as the screw holding turn signal lever.  Lift the assembly out of the way.
  2. Remove the ignition lock cylinder. Look at the inside of the column housing just above and to the right of the center shaft and you should see a small vertical slot.  This is where the ignition lock catch is.  Insert the key to the ignition lock and grip the bezel of the lock assembly. Using a flat blade screwdriver gently press down into the vertical slot to release the catch.  The lock assembly will easily slide out. 
    • Place the lock assembly on a clean work area so as not to lose any of the small pieces that will be removed from the lock.
  3. Disassemble the lock cylinder. The following applies to both the old lock assembly being removed and the new lock being re-keyed for replacement.
    • At the end of the lock cylinder is a pressed on retainer that limits the amount that the key can be turned in either direction.  Carefully remove the retainer and set aside. 
    • On the other end is the key slot and grip/tab bezel.  Behind the bezel is a spring washer and an indexing washer that aligns the detents to the brass pins in the housing.  Insert the key and rotate the cylinder to the accessory position. Pull back on the index ring and look at the upper part of the housing to see the tip of a brass pin against a nub cast into the cylinder. 
    • Using a very small screwdriver or paper clip, push the pin in while applying a small amount of turning force counter-clock wise on the key.  Turn the cylinder about one eighth of an inch and stop.  The cylinder will pop out a short distance. 
    • Back to the other end of the cylinder, look inside to see a brass pin with a black plastic piece in the center of the cylinder next to the brass pin.  Press slightly on the brass pin and then using a sharp pointed object slide the black plastic piece over the pin.  The cylinder will now slide out, but be careful not to let the two brass pins and their springs in the housing fall out. 
    • Now remove the key and locate a rectangular sheet metal cover plate on the cylinder.  Using a small flat blade screwdriver lift each end of the plate slightly alternating each end until it easily lifts off.  Be careful not to drop the small springs under the cover. 
    • In each slot is a brass plate, there are six, sometimes five but with six slots.  Insert the key and tap on the cylinder causing the brass plates to fall out. Each brass plate has a notch on its side that lines up with a ridge on the under side of the locking block on the opposite side of the cylinder from the spring cover plate.
  4. Re-key the cylinder. Unless you have a key chart and number guide for the brass plates you will be setting the plates by trial and error.  Insert a plate in the first slot and insert the new key.  Place a small amount of pressure on the plate using a small screwdriver. If the locking block drops down flush with the cylinder, great you have the right one. If the locking block stays above the cylinder then you will need to try another plate. Make note of were the notch in the brass plates are so that it will help in fitting the next one.
  5. Re-assemble the cylinder lock and install. Now that all the plates are set in order place one of the springs that you took out earlier over each plate.  Then carefully slide the spring cover down into the slots at each end.  Make sure that it is completely flat, then “stake” the ends by putting a short handled flat blade screwdriver on the edge of the metal next to the spring cover and tap with a hammer to form the cylinder metal down onto the edge of the spring cover.  If this is not done, the cover may work its way loose and lock up the cylinder making it useless. 
    • Check the cylinder housing to make sure that the brass pins and springs are in place.  Slide the spring washer and index washer onto the cylinder bezel, then line up the locking block on the cylinder with the slot on the housing and slide the cylinder in. 
    • If you feel resistance, it may be the plastic catch on the side near the back of the housing blocking the cylinder.  Just lift it out of the way and the cylinder should slide in the rest of the way. 
    • Check the lock for rotation and the removal of the key, several times.  Now gently press the limit retainer back on the cylinder and install in the steering column by gently sliding the assembly into the opening until it snaps in place.
  6. Re-assemble the steering column or tilt wheel.
    • For the steering column, put the turn signal assembly, horn ring and steering wheel back in by reverse order.  It should be noted that the horn ring and steering wheel have small teeth or ribs that are cut so as to line-up on the center shaft a specific way.  Do not force these pieces on.  Install and tighten the locking nut and set the horn pad in place. Reconnect the horn or battery.  Job complete.
    • For the tilt wheel, if you do not have the special GM tool to install the snap-ring for the horn ring then follow these instructions.  With the horn ring set over the bearing compression spring and aligned, place the snap ring over the center shaft loosely.  Now place the steering wheel locking nut on the center shaft until fully threaded. 
      • Place an 11/16” open end wrench under the locking nut, then place a piece of wood or soft metal, less that 3/4” thick between the open end wrench and the horn ring.  Using the open-end wrench as a lever push down on the horn ring slightly.  Use your thumb to press down on the opposite side of the horn ring so that it will move down over the shaft evenly.  #** Repeat this process until the horn ring is below the snap ring groove cut into the center shaft.  While holding the horn ring down with one hand, push the snap ring down the shaft evenly using a flat blade screwdriver until it snaps in place. 
      • Release the wrench, remove the locking nut and place the steering on the  shaft.  Install and tighten the locking nut then set the horn pad in place.  Reconnect the horn or battery.  Job complete.

Tips

  • Take your time! Allow several hours to complete the job and be patient.

Warnings

  • If the spring cover plate is not staked properly it will detach and lock-up the cylinder rendering it useless.

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