The Detroit Truetrac 912A553 is a clutchless gear-based limited slip differential for the Chrysler 8.25" 29 spline axle. It works in the rear of 2002-2007 Jeep Libertys, but is incompatible with Dana 35C rear axle found in some 2002 Jeep Libertys and might be incompatible with the ESP system found in all 2006-2007 Jeep Libertys. Its gear-based carrier replaces the stock carrier. Ring and pinion gear set up is required.
There is also a version for the Jeep Liberty's front D30a. As with any other limited slip device installed in the front differential, it will make steering slightly stiffer and cause the steering wheel to spring back to center more quickly than usual.