By rubber hanger, you mean the round bushing, right?
Does it bang from side to side on the bumper?
If it's worn out, it has lost it's rigidity, so get a new one.
Has it always been an issue? If it's a design issue and just too close, getting a new one probably won't solve your problem.
Stop by your local scrap yard and pick one off another vehicle.
Just bring your existing one as a reference and get one a bit longer.