How do I find out if the rearend has Positraction?
Positraction rears are supposed to have a tag reminding you to use a special GM friction modifier when you change the fluid. This tag may come off. If the tag is missing, jack up the rear of the vehicle and spin a rear wheel. If the other one spins the same way, you have Positraction (or a locker or spool or something!). If it spins the opposite way, you have an open (regular) rear. If it doesn’t spin at all, you have a problem (locked up brake, broken axle, etc.).
