As
RSBAD454 said, limited slip is positraction. It is just the name that GM calls their limited slip. Just as Dodge call it Trac-Lok.
There are 3 types of differentials. (releases the inside tire on turns)
1)open - ex stock carrier
2)limited - clutch or cone type (GM option was G80)
3)locked - aftermarket only Lock-Rite, Power-lok, ARB is a air actuated locker that operates like an open (differentiating in turns) and locked when air is applied.
A spool doesn't differentiate as the axles are locked together, so it isn't actually a differential.
Chris Lucas
www.73-87chevytrucks.com
www.captkaoscustoms.com
Project Su
Jimmy 2WD Project