Interval wipers are an option that was available from the factory on the pickup line that started in 1973. This article will focus on how to retrofit a factory interval wiper system onto one of these trucks. The advantage to interval wipers is increased safety if you experience fog or mist in your area. You can set the wipers up to wipe intermittently without having to remove your hands from the steering wheel. The part required can be had at a salvage yard or are still available new. When I priced it at the local parts house they wanted $50 US.

The advantage to using the factory setup is ease of installation and sanitary appearance. It really is not readily visible that you have added an interval wiper system. The only thing required to install the system on your truck is the interval wiper switch and the integrated control box. It is the electronic box that controls the delay interval. The switch in wired to the box and the harness transfers from the old switch to the new one.

1. Begin by removing the knobs from the headlight and windshield wiper switches and the radio. 2. Remove the bezel from around the radio. 3. Remove the 6 screws from the bezel around the instrument cluster and remove the bezel. To remove the bezel it may be necessary to remove the air conditioner duct and the lamp that illuminates the headlight and windshield wiper switches. 4. Remove the nut that holds the windshield wiper switch in the dash. 5. Remove the old switch and disconnect the two electrical connections. 6. Plug the two electrical connections into the plug on the delay controller box.

7. Install the box and mount it to the inside bottom of the dash.

8. Install the switch in the dash and reinstall the nut to secure it. 9. Install the ground wire to the screw that holds the other ground wires behind the instrument cluster. 10. Check the operation of the interval wiper system. Turning the switch to the right should access the low and high speed functions. Center is off. Turning the switch to the left accesses the delay function. 11. Reinstall the bezels for the instrument cluster and the radio. 12. Reinstall the control knobs for all switches.