Depending on what condition the locker is in, and when it was put in, etc. the locker itself is worth at least $300-$400. Cost me $550 to get a brand new one for my 10-bold corp. axle. Make sure the carrier bearings are in good shape. If they're not good then it cost $300+ labor to get new ones put in. The bearing set for those is monsterous, and expensive. Gear sets range from $200 to $400 new. Used they're probably 1/2 that if the wear patterns are good.
If I were to sell just my third member now I'd want at least $1000, because it has a brand new locker, new 3.90 gear set, and new carrier bearings with rebuilt carrier. It's good for another 30 years of life.
If they want more than $500 for it I'd have it checked out by a shop you can trust (since its removed anyway).
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'69 3/4 ton C20 2wd w/ 350ci/400THM and a wood bed!
'69 3/4 ton Custom 20 2wd w/ ORIGINAL 350ci/4sp Manual and a wood bed (parts beast).
Seattle, WA.
*See pics of my trucks and project at
www.webshots.com!