Nobody knows... Help!!!!!

I have a 2004 Dodge Ram 1500 with the 4.7
V8. Two weeks ago it was misfiring and the
check engine light came on. I scanned the
codes and it was cylinder 1 misfire.  I
replaced the coil pack and it was fine.
Similar thing is happening now except there
is no check engine light. I still had it scanned
and put under the "calander misfire" and
while driving and misfiring it did not show.
Mechanic said that it had to be a really bad
miss for it to show unlike ford or Chevy. I
replaced the same coil pack as before and
no change. The misfire very specific, when
the truck is at low rpms under load. It does
not misfire at idle. tried a can of sea foam
and although the smoke looked cool it did
nothing to the misfire. I have changed all the
plugs and wires within the past year. I was
told to look at the mass air flow sensor and
that seems fine. Also, there is no oil on the
plugs. The fuel filter is a lifetime part and in
the fuel tank so I haven't looked at that.

I am stumped and have herd of this exact
thing happening before but can not find a
solution. Have talked to many mechanics
and they are stumped too, PLEASE HELP!!!
I'm desperate.