[Dave12]

It appears that I need a new tube even though I can't locate a leak when held under water. My question is the tube we use the 11/400x5 tube displayed in this link?
http://www.vansaircrafttires.com/products/11{47}400%2d5-Inner-Tube.html
Thanks in advance

 

[rvbuilder2002]

Nope.
All three wheels use the standard 500-5 aircraft tire which uses THIS tube.

The one you linked is only for the small nose tire on the 6,7,8 and 9A