I don't know if this is the minimum needed, but the ARB Twin Compressor is awesome. I tried to air-up the tire on my F250 with truck camper at a fueling station with a coin operated compressor. Wouldn't work, and in fact I lost pressure in my tires. The ARB works like a champ. I carry it everywhere I go in my truck. I've also used it several times to help other people out. Peace of mind. A tool for the road.