If you spin the wheels on an extremely slick surface, both will spin on a posi just like a locker.
Guess that's why the Fords have a switch, for those that don't know what to do with a locker. Don't buy a GM, those axles lock up automatically when wheels spin. Great feature unless you'd rather be stuck or don't know how to handle it.
Strange, always wondered why on earth some trucks actually came with open diffs, even to this day, but very rarely. Now I know.
Also, don't use an exhaust brake and god forbid, don't drive a vehicle without ABS, traction control and stability control. Them things are death traps without those features that keep ya from going in the ditch!
