[Yukon Jack]

My 69 K20 has a factory No Spin which is a Detroit Locker in the rear axle. It does make a bit of noise occassionally and the first few times you hear it surprises you and you wonder what that was - then you get used to it. Drive like special-K says and you'll be fine. Be aware that you are running a locker when it is icy or snowy out. I came out of a store drive one day and there was a little moisture on the road and got spun around about 90 degrees real quick when the rear axle locked up - that is the only time it has grabbed my attention.

I'm running a new Detroit Locker in the 14 bolt I have in my 70 K5 and I find I notice it alot more. If I'm on the highway and go to coasting I can feel it unlock and when I get back on the gas it definitely pulls a bit to one side for some reason. I think that is actually becoming less of an issue the more miles I put on that Detroit Locker.

Yes your going to have an occassional clunk but it is all worth cause when you need both wheels getting full traction - the Detroit Locker is there for you!

I've never ran a locker in a front axle, however, I think your question is directed at one in the rear axle anyway.