Its not a RH-5° because if they were to come apart, they would blow to the inside when mounted on the steering axle. What kind of truck are we talking about? What you are describing sounds like the setup on a 15" pickup wheel. If that is the kind you are talking about, you can't just hook an air chuck to them. You have to tap them while you first inflate them to get the lock ring to seat where it is supposed to. I've never seen that kind of setup on anything larger than a 3/4 ton pickup, but then again, I haven't seen everything.
