I have a 2008 F150 5.4 AT 3.73 2WD. 16,000miles. When I'm accelerating up to speed and doing so conservativly. The truck starts to shudder when it goes between 50 and 60mph. It won't do it when out of OD or when I press down a good bunch on the gas. Just in OD. You can feel it when the torque converter locks. It feels like it starts bogging down. Only when I accelerate easy, like gas saving pace. It feels like the truck is starving for gas or something. I replaced the fuel filter and no difference. I have done no mods either. It feels like there is a dead spot when I lightly push the gas pedal. It goes away if I push about 1/3 down. It has plenty of power but it just feels sluggish when trying to drive consevativly. I bought it used from a dealer with 14300 mi's on it about 2 months ago. So I still have some factory warraunty left. I'm taking it into the dealer Wednesday.

 

mine does this sometimes as well. its an 08. with 23500. done it twice in the last week actually. running level 2 with 87, timing adjustments, just changes in tc lock/unlock which had no effect before/after, truck occasionally shudders, opened the hood one time, looked like it was shaking pretty hard, shut her off, started her up and ran fine. sometimes i mash the pedal to the floor and that gets rid of it, but im afraid ill blow the engine in the future if i keep doing that. sluggish from a stop if it starts shaking.
done in both 70 degree cali and 110 degree vegas weather

possible misfire?

 

Mine idles fine and drives great, as long as I don't drive like an old lady. It also does it all the time. It's like your driving a car in 5th gear at 20 miles an hr and mash the gas. But like I said before it's only when the TC kicks in around 45or50 -60 when your lightly pressing on the gas.

 

Possible low-grade mis-fire (faulty coil pack).

 

mine will do it when the tc locks in around 45 in 4th. shudders a little like the engine wants to die on me/tranny wants to crap out, give it some gas and good to go

anyway the edge can check for a misfire, ive ran the dtc everytime my truck starts to shake, no diagnosis from it

sorry to thread jack

 

I guess I need to drive a little more aggresive.

 

I do not believe that dtc will find low grade misfires.

 

what should i do

go to dealer: i think i have a low grade misfire and my tuner couldnt find it

but really ill be heading in tomorrow to have them replace my power steering cap that fell off after their last service and have them look into it