I spoke with folks at Auburn Gear recently about their new ECTED (electronically controlled traction enhancing device) for the X. It's not currently available, but I wa blown off with the line, "we'll check in to the need for one in the market." When it's "off" it's a limited slip diff and when it's "on", it's a full locker. Unique in that it can be switched on the fly at any speed , no forks or pins to engage for full lock. (most of that blurb is from their advertising...) It lists retail for under $700 and I have called them evey week as someone new for two months now, expressing interest in it , and I suggest y'all do too www.auburngear.com