Was the 1955 First Series (Advanced Design) truck a 6 volt or a 12 volt system? The specifications sheet only gives battery and generator capacity in amps but no voltage.
There was a very nice 1955 First Series at the Barrett-Jackson auction last week. It had a 12 volt system. I could not remember if that was correct.
Was the second series that was introduced in mid-1955 a 6 or 12 volt system?
. All Task Force (1955 second series - 1959) were 12 volt unless you own a 1956 GMC task force school bus. The one pictured below came with a 6 volt positive ground system. The owner burned out several lights before I pointed out all the Generator, Starter, and bulbs were all 6 volts. It's hard to crank a 270 engine with only 6 volts. Last years parts were commonly used in school buses to keep the bid low. . . Lou .