When using gas shocks like KYBs (please I know their hard and no one like them) do you use the rubber bumper that goes inside the strut dust cover? I keep reading they are "not required" for gas shocks, but does "not required" mean you might use them or not?? Or is it absolutely that you do not use the bumper with gas shocks?

I do understand they are absolutely required for oil shocks, like Boges.

Want to order some parts, so hope someone can enlighten me on this. Thanks.

Ansbacher

i use them as an added layer of protection weather they are called for or not.

Any rubber bumper positioned between the chassis mount and the shock body acts as a compressible bump stop in case the chassis is lowered close enough to bottom out the shock at full compression.

If your vehicle is lowered that much, consider shortening the shock stem to avoid shock damage. Of course that means modifying the shock, possible on Bilsteins and Konis, probably not doable on KYB and other standard replacement shock.

Sherwood

I believe they are required for any strut insert to prevent bottoming out the strut itself and keep it from getting internal damage.
Sport struts, koni and bilstiens make them, have shorter internals so you can run a lower setup and not need the same height bump stop, but should use a shorter one.