Dropped my truck off because of a ticking noise co...

Dropped my truck off because of a ticking noise coming from the engine. Service could not figure it out so they called Ford. Final conclusion was that I needed head work done. I didn't like that answer so I took it to Auffenberg Ford. Service Tech put a stethoscope on left side of engine and then removed coil banks and discovered #8 spark plug was loose. Replaced coil and plug. Problem solved by Auffenberg Service! Service ticket said the coil and plug had to be replaced because of "improper installation." It was Jack Schmidt service dept. that had previously replaced the plugs and coils.