GQ banging noise under drivers floor area

G'day GQ ers,

I have had a noise coming from under my GQ for a few months, sounding like metql banging on metal, sometimes when I first take off, sometimes when i go onto a dirt road, sometimes when I went up or out of my driveway, and its been driving me crazy. Hasn't affected the performance of the vehicle, a TD42.

I am aware of the fire wall and floor sometimes causing the problem and sometimes the body mount rubbers.
However, my mechanic found the cause of the problem in my vehicle yesterday, by accident, and I was wondering if anyone else would like to try our simple fix, before spending any money.

cheers
Tony