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| | | | Joined: May 2005 Posts: 323 Shop Shark | | Shop Shark Joined: May 2005 Posts: 323 | Hey guys,
I was looking at 56 GMC 1.5 ton with the 6 cyl motor in it. The guy said this truck had a 6 volt system. Does that sound correct? All my 55-57 1.5 and 2 tons are 12 volt. | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 |
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jun 2005 Posts: 221 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2005 Posts: 221 | I think it should be 12 volt BUT GMC did things a little different than chevy sometimes i had a 55 second series 3/4 ton that was 6volt | | | | | Joined: Apr 2002 Posts: 1,571 Shop Shark | | Shop Shark Joined: Apr 2002 Posts: 1,571 | It should be a 12v. The last 6v GMCs were the '55.2 I6 models.
Of course, if it has an I6, and was mistitled as a '56 (sometimes they were titled by year of sale, not model year), it could be 6v. Check the body number at the website in my signature. | | | | | Joined: Feb 2000 Posts: 587 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 587 | I believe GMC held on to 6 volt one more year than Chevy did. Weren't they Positive ground too? Pull a bulb and check the numbers on them. Think a dash bulb of 55 is 6, or back of headlight should say voltage if you pop one out. Generator tag sometimes says? OR color of it means something.
G.L. Grumpy's
Old Iron Ranch
Huntington, IN 46750
MM R tractor, Speedex
and Power King tractors
| | | | | Joined: Sep 2003 Posts: 23 Wrench Fetcher | | Wrench Fetcher Joined: Sep 2003 Posts: 23 | if it's a 56 and 1 1/2 ton its 12 volt. the medium duty trucks were all supposed to be 12v that year.
John
| | | | | Joined: Apr 2002 Posts: 1,571 Shop Shark | | Shop Shark Joined: Apr 2002 Posts: 1,571 | All 6v GMCs were positive ground. V8 '55.2 GMCs were 12v negative ground. | | | | | Joined: May 2005 Posts: 323 Shop Shark | | Shop Shark Joined: May 2005 Posts: 323 | Well it's home and its a 6 volt alright. The fun begins..... | | | | | Joined: Dec 2002 Posts: 2,549 'Bolter | | 'Bolter Joined: Dec 2002 Posts: 2,549 | How many cells does the battery have. 3 cells = 6 volt, 6 cells = 12v. | | | | | Joined: May 2005 Posts: 323 Shop Shark | | Shop Shark Joined: May 2005 Posts: 323 | It didn't come with a battery but the light bulbs are 6v. | | | | | Joined: Mar 2005 Posts: 6 Junior Member | | Junior Member Joined: Mar 2005 Posts: 6 | i have a '56 gmc 1.5 ton and its 12v | | | | | Joined: May 2005 Posts: 323 Shop Shark | | Shop Shark Joined: May 2005 Posts: 323 | All signs are its a 6 volt and we're gonna keep it that way. Thanks for your help. | | |
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