Tag axle question

[The_Stuff]

like this?

I hear they are air ride... could have air pump issues. good luck getting an alignment done on that for cheap!

 

[lapeer20m]

A tag axle on this style bus seems like all kinds of problems just waiting to happen!

It is unlikely that the extra axle was installed by ford. My guess is that the company that installed the axle does not have the same research and development budget as ford motor company.
My experience with ambulances over the past 10 years or so is that when the chassis from one company gets married to the body from another manufacturer there is always unhappiness. The more complex the add ons, the more problems you will suffer down the road.