How big a problem, plug blowing?

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Jun 8, 2007 | 10:40 AM

#31

machinist man

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From: Northern MN

I think Ford changed the spark plug design in 2002. I say this because I recently changed the plugs in my 2002 F150 5.4L and they had around 3/4 inch of thread on them. Back when I had my 98 with the 4.6, I changed plugs on it and they only had the 4 threads. I never did have any problems on the 98 before I traded it on on my 02, though.

Last edited by machinist man; Jun 8, 2007 at 10:55 AM.

Jun 8, 2007 | 12:12 PM

#32

LxMan1

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From: Louisville,Ky.

The heads didn't get more threads until sometime in the 03 model year.

Jun 8, 2007 | 05:28 PM

#33

machinist man

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From: Northern MN

So did they have more threads on the plugs than in the heads on the 02 motors?

Jun 8, 2007 | 10:22 PM

#34

LxMan1

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From: Louisville,Ky.

Yep, they do.

Jun 22, 2007 | 11:21 AM

#35

Machinator

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Never heard of this problem.

Jun 25, 2007 | 10:06 AM

#36

krewat

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Joined: Jul 2002

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From: Long Island USA

Just caught this thread.

Here's some dates that I got from a Ford document, not sure about the accuracy, but definitely seems to be about right.

There are two steps to improving the heads - an "alignment feature" built into the head to help align the plug correctly at the factory, and the "long thread" heads.

December 1996 - 4.6L 4V head alignment feature added.
February 1997 - 4.6L 2V head alignment feature added.
September 2000 - Windsor 2V head alignment feature modified (4.6/5.4/6.8)
November 2002 - Windsor 2V long threads added (4.6/5.4/6.8)
May 2003 - Romeo 4V long threads added (4.6/5.4)
November 2003 - Romeo 2V long threads + modified alignment feature.