ok i have a 2004 f150 with the 4.6 in it and once in a while when i slow down and speed up again it feels like my trans doesnt know what gear to be in and like jerks and stuff. it mostly happens around 45 to 60mph any idea why it does that? and some times off a take off my truck will like hardly move like its not getting fuel or some thing.

 

Before looking at the trans, I'd consider misfiring first. How many miles on the truck, how many miles on the plugs (and what brand), and have you ever replaced any of the coils? When was the last time you changed the fuel filter?

 

not sure how many miles on the plugs and brand. i was gonna change the plugs and fuel filter when i hit 100k im at 98k now

 

Do it now. Use Motorcraft plugs.

 

should i do plugs and coil packs?

 

No need to do coils unless it's still missing and it's determined that it IS a misfire and not something else. Before Brew jumps in here and chews you out, you do not have coil "packs" - you have COP (coil on plug).

Do not use antiseize on the plugs and torque them to 28 ft/lb, and use dielectric grease inside the coil boots.

 

yeah I think you are supposed to change ur plugs at like 70k...lol
Im at 83K and still no problems but Im going to replace mine next week.
I dont like waiting for something to break to fix it.

 

The current recommendations from Ford are 100k plug changes except on the 04-08 5.4 3V with the 2 piece plugs, which are 60k.

However, the factory plugs only made it to 84k in my V-6.

 

yea i was told to do them at 100k. i need to do to much work to this truck. new brakes, new tires, plugs, i was thinking about flushing the rad and trans 2.

 

Same problem I had. Had a misfire in the number 8 cylinder. Replaced the plug and coil, problem went away. Unfortunately my 04' is only at 55k miles, soon I'm just going to replace the other 7 plugs and coils....sigh, ain't cheap.