Not very common with that year, usually 03/04, with 4.6 engines see highest failure rate. This usually happens after the engine has been overheated severely. Just make sure the cooling system is in good working order and watch temps closely.

I've over heated my 01 Dll 4.0 twice now...with no serious issues. First time, she was in the red and it was 3:30 in the morning and l was a mile from work. Said screw it...l'm driving her on in, if she blows, she blows. Idler pulley had seized and took out the belt. Made repairs, refilled...no lingering issues. Second time, the top hose portion of the thermostat housing cracked off, but l caught this issue before the gauge pegged. Repaired, refilled, drove eight hundred miles home...no issues. Now, l don't recommend this haphazard style of driving...but this just goes to show you that the older engines have a bit more tolerance for mishaps.

Brian.