Ok, I need a lil help if anybody has an idea what this could be. I have a '02 F150 FX4, 5.4L with around 158k on it... When it shifts from 3rd gear to O/D, and I'm driving in the range of 45-60 mph, there will be a violent jerk or two, then it will stop, and it'll happen again a few seconds later, if I'm still in 4th gear... this mainly happens when I'm pulling an incline, even a slight one. When I shift down to 3rd, it doesn't happen, and if I'm going 65mph or faster it doesn't happen... I thought it might be a tranny problem, but I've noticed a very very slight skip in the engine with I start driving from a stop. So maybe new plugs??? Thanks for any insight!

 

Would do plugs and replace boots on cops. Could be a bad cop or cracked boot. Would change fuel filter as well.

 

My 04 was doing the exact same thing w/ 87k miles on it. New spark plugs fixed it 100%.

 

Thanks yall. Thats what I was hoping to hear. A few spark plugs are a whole lot cheaper than transmission work! Haha

 

Same issue here with my 00 5.4. It's not the first time for me with those issues. Last time it was a COP that had a little dry rot. Mine hasn't thrown a code but it sure is annoying isn't it?

If you replace it yourself, don't make my mistake (and you may be much more experienced than me and know this) I had a COP go bad on my way home from work. pulled into advanced auto, bought one, and started to change it right there. the dern bolt that holds it down snapped because it was so warm. I won't do that again.

 

i have had that same problem come in many times on customer cars i change all the boots and plugs i also like to change the fuel filter and clean the throttle body