After reading the comments on this Forum an my own experience I think that the Rack Damper Screw/Bolt was ment to reduce the shake on an engine with no other issues going on (as in new car). So, depending on the condition of your Engine and what supports the engine replacing it may or may not help.

I bought a newer (Gold) Rack Damper Screw and found it did not help much until after I took care of the Valve Adjustment, rebuilt the Injectors and replaced Rubber Engine/Transmission mounts and 1 Engine Shock.

After the above was in order I was able to remove a little more shake with the Rack Damper Screw. (Still have not re-timed my IP maybe doing that will get rid of some more shake).

When I compared my old Damper Screw to the new one I found that the tip if the plunger on the old one was worn and that the spring on the newer one was almost 2X as strong. So it may be that updating to the newer style could be helpful if the older one is worn and the spring is weak.

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84 300D, 82 Volvo 244Gl Diesel