Fill up air in inner wheel

What I did was used tin snips to cut a slot (1/2" wide X 3/4" deep) in the chrome rim over the stem and then bent the cut down and back so the edge was rounded. That way I could see the stem and it was easier to attach and hold the truckers style air gage, or the fill up hose. This was all before I bought brass extensions. The kind you install when you're putting on new tires so they're part of the wheel. They don't go bad often. Cost $70 for two sets for the rear duals but they were well worth it. But they did need the cut in the chrome rim to make them more easily accessed too so it worked out well.

Air-through valve caps are well worth while for the inner (and outer) duallies. A proper dually chuck is essential. In many cases, getting one where the far end for the inners is straight-on rather than at an angle may work more easily.

Duallies are rather an annoyance to maintain, to be honest, but probably better than most of the other options overall.

X3 on the extenders. I had three go bad in a matter of months. I finally bit the bullet and put on dually solid valve stems. No more leaks and easy to adjust the tire pressures.

To the OP, unless you have a truck-style air chuck, you probably won't be able to get air into that inner tire.

Mandalay Parr wrote:
You need to get a Trucker type air nozzle. It has an offset head just made for duals.
I would stay away from valve stem extenders. That can be a source of leaks.

True on valve extenders, they also don't play with tpms. I've had 2 extenders go bad in a matter of months.

You need to get a Trucker type air nozzle. It has an offset head just made for duals.
I would stay away from valve stem extenders. That can be a source of leaks.

Don't know what kind of Rv you have but you'll need a longer air chuck, or install valve extenders. I am surprised they didn't come on your MH.