Is it legal to drive with tailgate down in Pennsylvania?

Question

I want to haul a motorcycle in the back of a pickup truck that only has a 6-foot bed, and to be sure the bike fits I will probably have to keep the tailgate down.

Answer 1

Yes it is legal. All that is required is to insure the load is secure. A flag is only required when hauling long objects like lumber, pipe or other items that protrude and could strike a vehicle traveling behind before it contacted the bumper.

Answer 2

Yes it is legal  

Answer 3

Only if you have a flag ( or a red cloth) showing that the gate is down and your load extends past the bumper. I would't however go on the Interstate like that though.