Should I convert to 12 volts?

October 1, 2008 | By Richard Prince


I currently have three 1948 Ford F-1 pickup trucks and I intend to consolidate the best parts of each into one good vehicle. All three of the trucks operate on a 6-volt system, and I am trying to find out if there is a benefit to converting the one I build to 12 volts or if I should retain the 6-volt system. If it is beneficial to convert to 12 volts, is there a good guide to detail the process?


There are a number of advantages to converting vintage vehicles to 12-volts. The main one is that they often start easier after conversion. If you want to utilize any modern electronics, such as a stereo, CD player, air-conditioning system, satellite navigation device, etc. it is obviously advantageous to have a 12-volt electrical system.

Converting is relatively simple given the simplicity of the electrical system in a 1948 vehicle. You need to think about every component in the electrical system and change or modify those that need it. That means changing all of the bulbs, starter motor solenoid, ignition coil, adding a ballast resistor in the ignition circuit, changing or modifying the gauges, or protecting them with something that reduces the voltage back to 6volts (such as AC Delco voltage reducer part #U1745), etc.

There are numerous automotive electrical books currently in print that you may find useful, including “How to Diagnose and Repair Automotive Electrical Systems” by Tracy Martin. These books are available from Motorbooks International (,, and major retailers such as Barnes& Noble.