Hello, I have a '79 Blazer with a GM-Corp, 12 bolt, 8.875" ring with factory govern-loc. 160,000 miles. It sometimes gives a 'clunk' between forward and reverse, and a much more mild clunk taking off from a stop. I had hoped it needed U-joints, but I'm not that lucky. I took the cover off to look it over. First thing I noticed was that it was on with silicone, so who knows what's been monkeyed with. The yoke can rotate about 3/8" before the ring is engaged, so the backlash is screwed. The yoke will not move verticaly or lateraly, and it's not leaking oil. I flexed the planetary gears a little with a screwdriver; there's a fair amount of slop in the carrier. The Govern-loc works fine. I was contemplating a low-buck rebuild, but ran into a few snags. Can't find a carrier kit for the Govern-loc; only for open diffs. Looked into a Lock-Right, but National Drivetrain says the one for my axle is meant to go in an open diff and wont fit my carrier. So now it's all the way up to an Eaton unit. Do do the rebuild , I'm looking at: $140-$150 Ring and Pinion $80 -$100 Bearing/Seal/Shim kit $350 Eaton unit. I can ride on this one for long enough to make my decisions. Before I throw ~$600 at the GM-12 bolt, I figured that I'd ask the forum. Should I be looking to go a different route? Different axle? Different components? Advice and personal experience appreciated. Thanks, Fletch.