i recently installed 95 mustang rear shocks on my 2dr tracker, so far so good. they ride rougher than than my crown vics did for sure but might be a little smoother with the extra weight of your 4dr model as they ride nicer with some weight loaded in mine. the mustang shocks are about 1.5inches longer extended and when compressed are the same length as the crown vics. these shocks also bolted right up with the stock bolts, there was no need to find a sleeve for the bushing like on the crown vics.