Should. My 1984 300D had both when I got it. No emergency, and I doubt you will notice a difference with two. Bring a set of small ignition wrenches to the junkyard or you will never be able to remove the lower lock nut to remove it. I recall the 300SD use the same shock, but the upper mount is different (inverted for more space or such). Most upper mounts are degraded. I filled the gap w/ black polyurethane (PL1 gutter seal from Home Depot), which seems to last.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans