aftermarket does do something, the jacker bolts hold the caps in place as on a hard launch or acceleration, the pinion tries to push the ring away which can stress the caps. if the bolts stretch just a little bit or the caps break say good buy to every part of the pumpkin including the ring and pinion. plus it does make it easier to change the fluid.

o and yes it smells like A$$

 

i have a TA girdle in my garage somewhere waiting to go on my car

http://www.drivetrainspecialists.com.../girdle-1.html