It always happens when the car down shifts and is slowing down, I was wondering what could it be?

Diff mount? Diff bushings? Motor mounts? Also you can feel the transmission clunk a bit to when at slow or awkward shifts

There is also a harsh and sudden clunk when going into reverse, it pretty violent too.

I think I have a compounding problems with mounts and bushings.

Also when push comes to shove, what tools do I need for the corresponding jobs? These clunks are driving me crazy.

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.