[Gustav]

Well they should be shimmed correctly from the factory but some companies are better at this than others.I would just run them if they feel and sound OK.I normally just run complete diffs as they are unless they feel horrible.

if you push and pull on the outdrives and there's not alot of backlash and they spin nice enough so the mesh isn't too tight then they should be fine.

When you use something like hybrid bulks or the UE ultralite cases they need alot of setting up since they're made to fit different diffs.The stock diffs are made to fit those cases and they probably just use a set number of shims so apart from tolerances they should be good.

Basically you want the ring and pinion mesh to feel and sound right(not to loose and not too tight) without alot of slop between the bearings or preload on the bearings(too few or too many shims)

If they did need it then a LHS or Mike would get you shim sets.