Two problems related to catalytic convertor have been reported for the 1997 Ford F-150. The most recently reported issues are listed below.
Heat shields loose on the catalytic converter. Two clamps were replaced again. I had this fixed 2 years, previously. I was charged $70. 50 for this to be corrected again. It seems that there is a problem with the quality of the clamps that are being used by Ford.
Design of the catalytic converter and shield allows for accumulation of grass and other debris, fire resulted from grass burning.