Just installed Yukon 5.29's with Spartans front and rear in a V6 IFS truck. Needed a little assistance from Zuk, with is a great guy to work with by the way!!!! My concern is that the driveshaft has about 1/8 turn play in Neutral (5 speed). The gears are set at .008 perfectly and if turning the driveshaft ever so gently you can feel the very little backlash but then you can turn it quite a bit before it engages and loads up. It turns about 45 degree which would be around 1/8 turn. My concern is the 1/8 turn of slack.

How much slack is typically normal with these style lockers?

I know the gears are perfect, and the locker was installed per instructions, so it should be right.
Turning on blacktop it scratches the inside tire every time so i know its locking up good. Its not quite as noisy as some of the videos ive seen but it does make a little noise.

Ohh by the way this gear set and housing took .115 pinion shim.....!!!! Thats where i needed Zuk to help. Ive never went that high and had concern of something i wasnt seeing, but nothing was missed. Just needed lots of shim.

 

Those lunchbox lockers have slop in them due to their design. I've ran quite a few of them and would have been stoked to only have 1/8 turn.

 

It's normal mine are the same

 

Mine in a v6 rear third has some slop, too. It's a little annoying with a v8 and a 5 speed, but so far it's holding up, and I'm getting used to it.
Driven maybe 500 miles with it on pavement so far, and one light wheelin excursion to test it out. Can't wait to really get into some hairy trails with it.
First gen pickup with no weight in the back can be interesting in the rain, but I'm learning to act like there's an egg between my right foot and the pedal