I have a Auburn Posi unit with 3:73 gears and its been working fine....I went around a slow slight turn in 2nd gear and punched it and just one tire spun! Whats up with that? I have never owned one of these units before and it was already in the car when I bought it.....is this normal? I can take off and burn both tires and shift second and still spin posi and catch posi in 3rd, so Im just confussed why only one tire would spin when I nailed it in this slight slow turn.....any help would be much appriciated !!
This unit is pretty new so Im lost as to why it would do this....

 

Your expectations as to what a posi actually does are inaccurate, it would seem.

A posi won't keep you from spinning the inside tire in a turn. What it will do, is to at least continue applying power to the other one while the one that has no traction is spinning. If the traction-challenged tire has less traction than the amount of torque required to break the axles loose from each other (around 60 ft-lbs or so in a typical street posi), it will rotate at the same speed as the one that does have traction..... which means it will "spin" on the pavement if this happens while in a corner.

 

yep your right! I just took it out for a beatin and it works fine...its just like you said under that certain pressure it makes sure that its not locked,Im used to my old Powertraxx even though that did somewhat unlock in turns too but not very often with the springs I had in it