[Chevelle-List] Outboard axle bearing going out?

[Galen and Melissa Love]

Hey guys, I could use some help.  I've got a noise in my rear axle.  It sounds like it's coming from the vicinity of the left rear brake, and I notice it most when I'm accelerating from low speed, especially when turning in either direction.  Most of the time it's a pretty mild noise, like there is a piece of something loose in the brake mechanism; but on occasion (especially if I try to accelerate hard), it will be a hard clunking noise with each revolution of the rear axle.   I pulled the left rear wheel off tonight and checked the brake out.  It appears fine, I can't find anything that has come loose that might be causing the noise.  I was trying to think of what else it might be, and I began wondering about the outboard axle bearing.  I did a rough endplay check on the left axle shaft, and I'm getting about 1/16" (0.0625") endplay.  This seems pretty loose to me, but I don't have a repair manual to know whether or not this is reasonable.  Does anyone know what the endplay spec is for a 12-bolt rear end?    Thanks in advance, Galen