Stovebolt.com Forums The Parking Lot Big Bolts New truck, 1961 gmc 5000

I have a '61 C60 with the 261 6 cyl.;I will dig some out but I couldn't find a pic right now. I lucked out that mine's all original bought from the farmer that had it since '64. He bought it from a local lumberyard that had several; they bought them all new and then traded the whole fleet in for new '64's with V8's. So it's almost kinda sorta a one owner. That front suspension you mentioned they only ran for two years, but parts are still available if you look. This site is worth a million $$ in the insight & info you will get! That V6 will pull anything you load up. My dad had told me that the GMC's prior to maybe '58(?) were positive ground but that they had standardized afterward. Might have more likely been when they went to 12v, which should have been '55. Interestingly, when I got my Chevy it was actually running positive ground! I called the excellent auto electric shop we have here and asked him what's the deal. He said someone had gotten it crossed up at some point and switched the polarity. Besides changing how your ignition parts wear and the danger of crossing jumper cables etc. it wasn't really hurting anything. I had called him about rebuilding the generator & regulator; he said pull them, bring them in and when you get them back switch your cables back to negative ground. I did that, all is back as it should be and running fine.

In 1956 GMC small trucks went to 12v negative ground as standard equipment.
12v negative ground was an option for 1955 Blue Chip small trucks (6v positive ground was standard equipment).

Here is 1955-1959 USA GMC Blue Chip truck documentation.

Thank you tclederman , Dad passed a few years ago and I still miss picking his brain on deals like this!

Sweet Man !

Several years back I bought a '67 GMC V5500, v6/4spd/2spd, It was a former moving van, converted into a potato hauler. It was well used and had been sitting for years, bought it, put a battery in it, turned the key and it started instantly, quiet, no smoke, no rattles, I drove it for several years, with absolutely no trouble, loaned it to a friend who wanted to use it for his construction business, said he had a CDL driver for it, after about a year I asked for the truck back and was told it quit running, It seems the CDL driver heard it start knocking and smoking and found the oil dip stick "to be too short to reach the oil"

Couldn't afford to fuel it!

Someone put oil in it after the damage was done with no oil.