stock spark plugs?

[blitzk]

What plugs does the factory put into 04 XLT 4.0 K-vin's?

I replaced my plugs today with Denso IT16 iridiums and just wondered if the plugs I took out were stockers or not.

 

[blitzk]

OK... so I think the plugs I had in mine were stock...


CYL 123 use Motorcraft platinum AGSF 22PGM (pass side)
CYL 456 use Motorcraft platinum AGSF 22PM (drivers side)

There is a noticeable difference in the center electrode.

Now my question is, why do they use 2 types of plugs?

 

[dannyb420]

Your correct they are the stock plug, I just changed mine a few minutes ago. The center electrode on plugs 456 are rounder the 123. Not sure why. I replaced with autolite double platinum and autolite professional wires. Not as hard as I thought it would be plug one was the only one that was a bit difficult to get a ratchet to.