My 2005 f150 started bucking at 48 MPH when I give it a little gas. Seems like it can not make up it's mind what gear to be in. If I push in the over drive button so it does not go into overdrive it is fine. This may not have anything to do with it but it started after a repair shop removed all the stuff to replace the plugs , they decided not to change them as they would not budge. I have 102000 miles on her. Any clues?

 

first of all you need to have your plugs changed. there is nothing wrong with your transmission.

imo its not likely they damaged a COP (coil on plug) while removing them.

if the truck wasnt doing this at all prior to the attempted spark plug change i think they may have cranked on the plug to break it free and ended up snapping it; then left it there.

just a gut feeling.

https://www.f150forum.com/f4/5-4l-3v...09-07-a-56871/

 

I cannot understand why it would only buck in overdrive, same speed every time unless I only press lightly on the gas. I would think a broken plug would not know if it is in or out of OD.

 

that happens right at the beginning of OD when the torque converter is locked. engine rpms are so low that with one plug missing youll feel it there the most.


an example would be my '99 mustang with a 5 speed and 4.6 liter. when i first picked it up the same thing youre describing would happen at 40 mph in 5th gear because at least one plug was missing. if you left the car in 4th at 40 you really wouldnt feel it, until you lowered the rpms to a few hundred above idle in 5th gear.

with the v8's you will only notice a single plug miss at 40 mph or idle, if youre looking for it.

 

will someone back me up on this one please.

i still have a buddy with the same stumbling (original plugs at 80k) who is convinced it is his transmission after talking with an older shade tree mechanic.

we'll get this question here about once a week. who knows how many "transmission" threads we have where worn out spark plugs are the cause.

 

sounds like a plug... or somethine along that line....

 

I have the same issue with my '04 SCREW with 189k. It is around 45 and I just start to accelerate slowly by changing the RPM a few hundred. It reminds me of a standard trans in too high a gear. Adjust the RPM to about 300-400 and I don't have a problem. My truck is not shooting a code about bad or worn plugs or COP. I just thought it went into OD and needs to be kicked out of it with a little faster acceleration. My dad's (sorry for the next word please forgive me) Suburban does the same thing.

 

change ur plugs and coil packs or find out which ones coilpacks are bad its not the tranny.

 

i know this is an old post but my 05 5.4 auto is doing the same thing. did you get it fixed? my truck has 106000 on it and it started about 2000 miles ago.

really can't afford a new tranny!

 

Just to let everyone know I had a issue with my 2005 F150 jerking. At speeds between 40 and 50 mph. It would jerk sometimes in OD only. I thought it was the transmission. It is at the Ford dearlership today and they told me I need my plugs changed and there is codes for a bad coil pack. They said it is not the Transmission. Bad coil packs, and plugs cause this problem they said. Ford also recomends changing in new plug boots and wires. I have 114000 on my truck. Orignal shocks, muffler, ball joints. Love this truck. Drives like a new one. Looking to put another 100,000 miles on it. I also have the Edge Evolution programmer and love how it works. I would like to thank everyone for there great info they put on this sight! Nice to see people helping each another! Take care everyone!