Resistor question

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WFarm

WFarm

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Getting ready to remove and paint the LH side inner fender on my 1975 Blazer and can’t determine what this large resistor is for. Truck came from factory with air, auto and 350 engine. Figure someone here knows for sure!

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bucket

bucket

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WFarm said:
Getting ready to remove and paint the LH side inner fender on my 1975 Blazer and can’t determine what this large resistor is for. Truck came from factory with air, auto and 350 engine. Figure someone here knows for sure!

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I believe that is the trailer brake power adjustment for an ancient brake setup. You could move that slider doohicky along the spring wire doohickys to adjust the amount of resistance. I've seen them, but never used them.
 
WFarm

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@bucket based on your lead I did a search for Vintage GMC electric brake resistor. BINGO! Mine is from a different manufacturer and not marked so obviously.

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Not needed but looks cool, like something from Dr. Frankenstein’s laboratory. Might detail it and keep.
 
squaredeal91

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WFarm said:
Getting ready to remove and paint the LH side inner fender on my 1975 Blazer and can’t determine what this large resistor is for. Truck came from factory with air, auto and 350 engine. Figure someone here knows for sure!

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Trailer brake?
 
WFarm

WFarm

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Yes, vintage variable trailer brake resistor. Don’t need it but too cool to not restore and reinstall. Proudly made in Michigan USA.


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