Can National Senior pass holders camp with an Rv for free? If so how many consecutive days are you can you stay?

Chris is correct. I think you can stay for two weeks, but the Shenandoah website should lead you to that info.

Call to clarify just to be safe

Very good

I would call and ask

To my knowledge, no. The campgrounds themselves still need to be paid for. The park pass will grant you entry into the park, but if you are at an NPS parkground you will need to pay