Why do these F 150 with the 4.6.eng have do many ign coil pack probs.

What is your question?

My F 150 with the 4.6 eng eats left hand coil packs like candy. I just replaced the fifth one. The right hand pack has never been replaced. The truck just turned 200k. I suspect Ford has a design prob which causes the left hand unit to overheat and fail. I also have a 1996 Ford CV with same eng which has 175k and has never so much as burped. Plug gaps etc are per Ford recommendations. What gives

What makes this problem better or worse?

There is no warning when the coil fails the eng runs rough and the check eng light flashes

How long has your 1998 Ford F-150 had this problem?

Began around 125k