Here is a test of AWD and 4WD.

[shays4me]

From what I've read on the various JK forums over the years, BLD is part of TCS, but requires the simultaneous use of brakes and gas to engage (which I think is why kojackJKU mentioned "pulling up the e-brake a few clicks").

Personally, I've never seen it work. When the open/open JKs that I wheel with get a tire in the air, that tire gets all of the power. I have seen a few videos showing it in action, so I have no doubt that kojackJKU's figured it out and has good luck with it.

Maybe my experience was positive because I have a rear limited slip. I was changing the oil with my son yesterday and wanted to teach him how an open dif works. I jacked up one wheel on the rear axle and expected it to just spin when I put it in drive. I was quite surprised after I turned off the traction control that the Jeep tried to drive off the jack. I've had power locks, posi's, trac-locks and eaton trutracs before and none of them would do that unless you applied a little brake. It acted more like a detroit locker then a limited slip dif. Naturally, after the oil change we went and climbed some hills!