At 100k I was experiencing a hard jerking that I though felt like the tranny slipping in low rpms under load especially towing. A few people suggested that I change my plugs cause I hadn't did that at the time. I changed them and the problem completely went away. Now almost 20k later its doing the same exactly thing again. I never changed the coil packs and didn't know if that could also be something to consider since I know its not my tranny?? It's an 04 5.4

 

What brand spark plugs did you use?

 

Oem

 

Any codes?

 

One or more of your 8 coils has failed. You dont have coil packs. if you have a cel get the code read and it will tell you what cylinder(s)

 

No check engine light and I looked up the codes on my gryphon anyways,no codes at all.....how much are the coils to replace, just to see if that's what it is as a check

 

E-bay has them. Search DG-508. The more you pay the better the quality may be..

 

Should I just stick to motorcraft or is there any better coils??

 

The 04 5.4 uses DG-511, not DG-508.

 

Don't buy off of ebay...Get good ones...I had the Globals and had nothing but problems.
I bought Borg Warners, and no problems..

 

thats right.

 

Do the coils sound like the issue since its doing the same thing as the plugs?

 

What about motorcraft, isn't that Oem??

 

yes motorcraft are OEM and if you can afford them they are probably the best. you can get them at rock auto at a discount.

 

Had the same issue it threw a code I replaced #6 coil with a Borg Warner, still had the same problem took it to my mechanic said #5 was bad too replaced it with another Borg Warner, turns out that one was bad out of the box. Didn't know what the problem was so I took it back and they replaced the "new" bad #5 coil and plug....Fyi you may want to just buy some extra just in case. I probably would of came out cheaper just buying a set of 8 from the start.

I was pulling my hair out trying to figure out what was going on. I didn't expect that a brand new coil would be defective. Hope you get it all back in working order.