This truck has 166k on it an I am noticing on hard surfaces it feels like its locking In an trying to drag a wheel in sharp turns. Otherwise I don't feel any slack in it transitioning from on to off throttle an I hear no sounds from it. I have heard these Dana's need freshening up around this mil . What do you guys say.

 

I would open it up and take a look. If it has fresh fluid and not enough friction modifier in it you will just wear out the shims that help provide the LS action....

If its something else you may be ahead of it...

 

What sixslug said.

I have 191K, but change oil and add friction modifier fairly normally.

 

Thanks guys after posting this tread I went on some Dana sites an it seems they all agree it should be gone through at this mileage . After looking at an reading about the way it should be done, my concern now is finding someone who will build it by the book. Setting all the preloads an ring an pion lash correctly. I live here in East Tenn between Knoxville an Bristol anyone know of good place in this area ?