Decks, Patios, Porches and Docks - Do I need to sand the deck?

Bought an older home last winter. The deck feels very solid but surface has a lot of deep gashes and splintery bits. We want to pressure wash and then stain/seal it with best protection affordable.

Should we sand it first? Seems like a lot of work and expense but don't know if surface will still be too rough after sealing if we don't.

Any suggestions on best protective staining product? Does the product seal or smooth the surface somewhat?

You could sand it enough to remove most of the splinters, but you're not going to remove the deep gashes. The nails or screws that hold the decking would all have to be countersunk before you could sand it. A good sealer, like Superdeck will penatrate the wood to prevent water from getting into it (which is what caused the spintering in the first place), but won't do much as far as smoothing the surface.

Thanks, Lefty. Does Superdeck also stain? If not, can you recommend a product that both stains and seals? Preferably semi-transparent. The deck is a fairly nice faded gray, I have no ideal what kind of wood it is.

Superdeck is a semi-transparent stain and sealer. A good variety of colors to choose from.