I've got an '06 F150 XLT with the 4.6l and whenever I am coming to a stop, it feels like it is downshifting too late, it shakes and feels like it is struggling before it downshifts into 1'st and sometimes even on 2nd. Its not like a violent shake or anything but it just vibrates and sounds like its in too high of a gear at too low of a speed. And, if I am just coasting at about 25mph and I very lightly touch the gas, it does the same thing, just a little bit of a rumble and vibration like its struggling. Its got 31k on it so its still under warranty, I brought it into the dealer because of this and the 4x4 light was not coming on(although it was engaging). I just got it back after they had it for 2 days and the 4x4 light works, but there is still the exact same problem with the transmission. I did not get a chance yet to speak with anyone with the dealership about it and they are mailing me the paperwork on what they did (I am about an hr away from them). I was almost thinking I am just being picky, but I really don't think this is the case, somethings not right. I used to have a '97 with the same motor and it had zero issues like this. Has anyone else had this issue or something similar? Any advice? I will be taking it back to the dealer, guess I will have drive it and point out the problem, although it is quite obvious.

And another thing, it only idles at 500rpm, is this normal? I have a Diablosport tuner and I bumped up the idle to 650rpm and it helped significantly, however it made the engine light come on, so I set it back to stock and it went back off. It did not throw any codes though.
Any input?

 

C'mon anybody? Anything?

 

Maybe post this in the Transmission or Engines forums. You might get better response there.

 

Good idea