When a RV trailer is equipped with a spare wheel & tire assembly that is different (steel vise allow wheel or bias ply vise radial tire) from the assemblies installed as original equipment, it’s intent is to be used for emergencies ONLY. It’s a buyer beware situation that should be addressed on the buyer’s PDI forms.
Note: It's addressed in the Keystone generic owner's manual.
Browsing this link may provide a solution.
https://www.google.com/search?q=conc...=1506382512626