Spark plug Champion or Motorcraft

Oem Motorcraft plugs are always my go-to. They generally last around 80k miles.

Modern Ford engines tend to work best with Motorcraft or NGK spark plugs.

Champion iridium. Champion makes the Mopar plugs. It's the closest thing to the original plugs without having to spend $30/plug.

Motorcraft is all I use , heard to many stories about aftermarket plugs causing misfires

I do run Motorcraft plugs because they seem to crack a little less than the Autolites.

anecdotally, my truck was at 226k when i changed the plugs. motor craft plugs coated, no anti seize, torqued tighter than advised. probably 20lb ft. 2 rear plugs were originals. i’m now at 235k and nothing wrong yet.

I have measured resistance above 5k and determined the plug to be causing a problem. Typical resistance is 1-3 kOhm, sometimes less for a new one.

Champion aren't a great brand. They may have been at one point, but not any more.

BEWARE O’REILLY’S AUTO PARTS CHAMPION SPARK PLUGS ARE WEAK AND BREAK AT THREADS AFTER HAND TIGHTENING AND THEN TIGHTENING NOT EVEN A QUARTER INCH OF A TURN, WAY BEFORE THE TORQUE SPEC AND THEY TWIST RIGHT OFF N BREAK.

Like everyone has mentioned just go back with an ac delco plug. I ran champions and had Mis fires, none of them were gapped right out of the box.