I got coils & plugs off eBay for my Dad's '00 F-250 w/5.4l and was sent plugs for the 4.2 and smaller mod motors. I was wondering if they're the same as the plugs for the 5.4l or not. I checked Motorcraft's website and they list them under different part numbers... just want to double check.

 

The 4.2L is a V6. The 4.6L and 5.4L V8's show a different plug when looking up plugs on Oreilly's website. The F150 4.6L takes a different plug than the 5.4L in the Superduty truck. I wouldn't use them, could cause internal damage to the engine if the reach is too long.

 

Bah... I knew it!

Thanks!

 

Modulars use a 14mm thread .708" reach plug. The OE plug for the 5.4L is a Motorcraft heat range 22(AGSF or AWSF22xxx),and the 4.6L's use one range hotter-a 32(AWSF or AGSF32xxx). The Lightning uses one heat range colder-an AGSF12FM1. They're all the same thread and reach,the heat ranges are different. There are half thread(AWSF),and full thead(AGSF) plugs-the full thread will work on any of the modulars,the half threads won't work on some of the newer engines that have more threads on the cylinder heads.
JL

 

doh, you beat me to it.

 

Interesting...

The plugs I got are AGSF34FM...

 

those are not correct based on the vehicle in your sig....'05 SD 5.4l. you should have PZT-1F-F4.

edit: actually, they aren't right for the '90 f150 either.

 

Those are the OE replacement fine-wire platinum plugs for the 4.6L 2V engines,not the '00 5.4L in your dad's truck. They'll fit,and they'll work fine,but the engine will be a bit on the ping-sensitive side from the elevated plug tip operating temperatures.
JL

 

imo, i'd return them and just get the right ones.

 

What is the difference:
AGSF32FM, AGSF32FSM, AGSF32FCM ?

(or colder AGSF22FM, AGSF22FSM, AGSF22FCM?)

 

heat range and tip type

 

?
Heat range is the same: 32
tip type too...