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Rear axle swap

SMB58

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SMB58 New Member

SMB58

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I have a 1988 GMC C1500 that I inherited from my father and I have been restoring and fixing it up for a couple years now. I would really like to put a locker rear in it. My rear code is GU4 (3.08). I understand that the locker code would add a G80 to that. Is this correct? All I should have to do then is scour used parts dealers for a truck with G80 GU4 RPO codes and swap the whole rear? Any help would be appreciated.

Badass69 Senior Enthusiast

Badass69

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Posted

If you really want 3.08 gears still you could. I would honestly just swap the carrier on your one you have now.... finding those trucks with 3.08's in the bone yard isn't going to be easy.... and a lot of them will be open. Not to mention finding a 25+ year old Gov Lock that actually still works would be a needle in a haystack. Really you could regear it too.... unless you really want the 3.08 gears for whatever reason. Is the truck a Turbo 400 or something? 3.42 even is a nice gear with a 700R4.

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