[Armada]

Just push the VDC button on the dash to light it up and turn the system off. Then launch the truck hard straight ahead from a stop on something a little soft. If you are on pavement and can break the tires loose, look to see if there are two stripes or one. If on something softer, look to see if the tires spun on both sides or just one.

If you have two stripes, then you have the automatic brake limited slip working.

If you try this with the VDC engaged, then the engine will bog down to try to prevent any slipping at all, and you will get a light flashing on the dash.

I believe that the ABLS - automatic brake limited slip and the VDC (electronic stability control) systems are related but independent. Turning VDC off, will kill the computer that controls all the "smart" stuff, like the pitch and yaw sensors that can send braking to individual wheels to correct oversteer, understeer, etc., and cut engine power as well.

The ABLS seems to be on all the time, even with VDC disengaged. What it does is work on that axle only. If it detects that the rear tire is slipping (turning faster than the other side), it will apply brakes to the faster wheel, transferring power to the other side, just like a mechanical limited slip does with a clutch pack.

Again, I could be mistaken, but I think ABLS is on at all times.

 

[Armada]

Any time.

BTW, a good limited slip that lets you send power to both rear tires is frequently better than a 4x4 with open differentials. That is because with open diffs like most 4x4's have, only the right rear and the left front receive power, even when 4wd is engaged. Most people don't know that only two wheels are pulling. With those systems four wheel drive is really a misnomer.

Serious off roaders modify their trucks by putting locking diffs in the rear (they are not highway friendly) and either limited slips or electric or air lockers in the front. I have a playtoy Jeep CJ5 set up that way.

I'd rather have a truck with a limited slip or true locker in the rear than a 4x4 with open diffs.

You should probably keep your VDC on also when in the snow, as it can correct a multitude of bad things that can happen when your steering wheel is pointed one way but the tires are not doing the same thing as your steering input is telling them.