Reverse in my 93 400E takes 3-4 seconds to engage, and usually grinds, sounds like marbles, when the car moves. Also, low-speed 3-2 downshifts (when slowing to make a turn, then accelerating enough to cause a downshift) are very clunky, a mild "bang." WOT 3-2 downshift is smooth, and normal to full-throttle upshifts and downshifts are smooth. The car has 165k. Should I wait for an eventual rebuild, or should I address the 2 issues I have now? It would seem the rest of the trans operation is flawless. What components need to be addressed, and how much?