The Stovebolt Site Forums The Shop Area The Electrical Bay generator chevy vs gmc

question.. outside of size of amps... whats the deal from gmc vs chevy generator... is there a differance.. and can either one be polarized just to work in a given truck... thanks Kat

Hy katrina, if the generators have the same frame (physical size) and pulley size, then yes they can be interchanged and polarized to work in either chassis, hope that helps.

Were the GMC's not originally positive ground and the Chev's negative?

Yes, but the only part that needs to have a dedicated polarity is the regulator. There's a difference in the arrangement of the cutout relay point material that causes rapid deterioration of the points if an incorrect-polarity regulator is used. The generator can be polarized to work either way without any concerns, other than maybe a part number mismatch. The actual generator is no different, regardless of polarity. Modern replacement regulators are often made to work with either polarity by changing a few internal parts. It makes it a lot simpler for parts stores not to have to stock both types. I'm not sure if a dual-polarity regulator is as efficient as a dedicated-polarity one, but they work well enough to keep the battery charged.
Jerry