Question about GMC G2500

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The alternator on our GMC Vandura with a V8 350 engine 5.7L locked and caught on fire. It messed up the plug in the back and by messed up I mean it was completely melted away. I purchased a new alternator and purchased a wire and plug set for the back at a GMC parts dealer. The problem though is that the wires on the new plug are all white and the two wires that have to be spliced with are two different colors, black and red. I have no clue which wire needs to splice with which wire on the new plug. The parts shop had no clue. I was told if I get the wrong wire in the wrong plug it could burn up the new alternator and I would have to buy a new one. Someone please help asap for it has put me into a position of not transportation and I need it for work.

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I can help regarding the polarity on my GMC 2500 Van alternator....
Facing the rear of the alternator, the red wire attaches to the screw terminal on the left. The black (grd) attaches to the screw terminal on the right. The top has a connector with 2 spade terminals. - one (left tab) is the "r" or relay terminal and the right one is the 'f' or field terminal.

Does this help... Red on left and blk on right....

Posted on Oct 18, 2009


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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: I have a 1995 gmc

You might find the pieces of harness at a salvage yard. Also you can use wire connectors available at ant auto store. Use a good crimping tool and wrap the splices with electrical tape.

Posted on Apr 13, 2011

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