2010 f150 supercrew fx4
While driving down the highway yesterday at about 65mph I went to change lanes. As I was changing lanes I gave it a little gas. About half way through the lane change truck jerked like I had just been rear ended. I immediately checked my mirrors to see if I changed lanes in front of some body. No one was around. Truck still ran the same. Everything I'be read seems like similar thing happen to others at slower speed.

 

a little or a lot of gas? the only time i have felt that is when i stomped on the gas and it felt like it went from 4th gear straight to 2nd and had a loud clunk and felt it from the rear of the truck forward.

 

Just a little gas. Just a slow steady pressure. I wasn't in any hurry so I wasn't putting it to the floor.

 

I'm guessing you have the 5.4 with a 6 speed? Mine is the 4.6 with a 4 speed, i'll trade you!

 

Your truck may be a candidate for a power train re-flash or you could have a valve body solenoid hanging up. Call the dealer and have them run your VIN for any TSBs. If it keeps jolting, take it in.

 

Here's the thing. Auto transmissions that shift smooth don't last as long as ones that shift hard. If I were to buy a new truck, which I am planning on, I would put a shift kit in it so the shifts are crisp and fast.

 

my 2009 did that every now and then. I had my tranny reflashed and updated and it still did it after a while. never hurt anything though

 

Mine did that when towing, back when I had around 6k miles on it. Took it in and had it re-flashed (They cleared all the codes) so I could have it re-learn my driving habits. I broke it in more aggressively and it's been much better ever since.

 

our parts truck here at work is a 2010 sc/6.5' bed 4x4 4.6/4spd. if your cruising on the highway around 55-65 or so and stomp on it, it will down shift from OD and SLAM into 2nd gear. I have mentioned about having it looked at before it either A: breaks or B: goes out of warranty but no one has seemed to care except me.

 

A slam into a gear is easier on the transmission than the smooth shifts.

 

My old '96 GMC Savana did that when the valve body and associated parts failed which was a chronic issue with the 4L60. (It went through three transmissions and SEVEN reman valve bodies under warranty between 50k and 66k miles when I got rid of the thing). The shifting like you were being rear ended was a symptom. I did have an old '70 Hemi Cuda with a full manual B&M Torqueflite that shifted that way on purpose, all the time, but that was a different application behind a 12.5:1 Hemi with a crossram manifold.

Good luck; I hope this is just a temporary or software glitch for you Ford guys.

George

 

in certain scenarios, yes. however this particular SLAM was in no way a "GOOD" slam. its enough driveline shock to cause the leaf springs to wrap and the whole rear end of the truck would shudder while going down the highway.

at one point I had a Built 700R4 with full manual valvebody and it had a hard shift and this is nothing like that was.