Interesting Take on Lighting Style Exhaust

[MTUH3]

Ford used the "lightning" style exhaust on non lightning model f150s during the same era. It caused excessive corrosion on the wheel.

May be he was talking about corrosion. He also mentioned it was not a very common occurrence, but to err on the safe side, the discontinued it on non-Lightning models.

Cold weather climates were the only places they saw issues also, by cold weather I think he was talking northern MN and other areas where the temp get below often in the winter.