We just installed a new floor in my mother's mobile home. The main pipe the toilet connects to isn't sitting on the floor. The flange on it isn't mounted to anything. The floor was installed with about a 2 inch space between it and all around the flange. The pipe itself is attached to a floor beam via a large metal strap. So the question is what do I do about the pipe giggling around. Does there need to be any wedges in between the floor and the pipe or what? It hardly moves around at all. So is it even really necessary?

I'm not too sure what the question is. Is the flange below the floor line? Is the closet bend "floating" so the flange moves around? Is the strap under, over or around the pipe? And last, Is what really necessary? Back to you, Tom

The flange is at floor height. That is if the floor actually was cut to go under it, but it isn't. The floor leaves a 2inch gap all around the flange. So its not an issue of being too hi or too low but it just doesn't have a floor to sit on because the floor wasn't cut to go under the flange.( a bunch of different reasons for that I'm not going to go into) I don't know what a closet bend is. What I do know is the flange attaches to a pipe then makes a 90 degree bend, after it bends the pipe goes under a beam where it is securely strapped to it. The strap goes around the pipe and around the beam. Its about 3-5 inches wide. I don't remember. But its pretty hefty. It was already like this before.
I was told that because the flange isn't attached to the floor the whole pipe attached to the flange will giggle ever so slightly and it does. So I was told to put a wedge of wood in between the flange and the floor. That was what I was asking if it is necessary?
Hope this helps. I have no experience doing any of this. So far I have installed a new floor, tub, extended the plumbing for the tub drain to reach the new tub, put in new drywall everywhere, new tub surrounds and finally need to finish off this flange, prime the floor and put on floor leveler before applying the final linoleum coating. ALMOST DONE!

" I don't know what a closet bend is." That's the pipe with the bend that the flange connects to.

"I was told to put a wedge of wood in between the flange and the floor. That was what I was asking if it is necessary?"
Not if the closet bend runs UNDER the beam. This will give the flange something to pull against as the closet bolts are tightened and in turn will secure the bowl to the floor. If you wish you may tighten the strap securing the bend to the beam so that you have no "wiggle" butIt sounds like all you really need to do is simply set the toilet. Good luck, Tom