Just got my 15x7 black steel wheels, and wonder if the stock lug nuts will do the job.

Whats the experience of those X owners with steel rim upgrade, regarding lug nuts?

The stock nuts have worked fine for me.

Not with the ones I got.

The stock lugnuts wouldn't work with my steel rockcrawlers... the wheel is a LOT thinner where it mounts to the lugs - so there is a lot more thread sticking out and the stock lugs aren't long enough to seat.

I don't know what the part number was - but when I got my wheels (at 4wheel parts) the guy grabbed a lugnut kit for me (the nuts are about twice as deep) and it worked fine.