My 07 4.0 sometimes vibrates when I'm driving it normally. When it starts vibrating if I Floor it for a second then it goes away... It will do this when I'm on Cruise Control, just normal city driving. But it seems not to do it when I drive aggressively...

Its like a faint thing that you can feel. Its just a little vibrating where my feet are and I can maybe feel a little by my feet.

Is this normal?

 

Yes, all of our mustangs vibrate in once place or another. My dash likes to vibrate, along with the doors and center consoles. Mainly because our whole interior is plastic.

 

Is your car a stick? If so it could be the flywheel. Had to have mine replaced at 2500 miles on my 07 for a strange vibration in 2nd & 4th

 

Its auto.

ALSO

I have another problem, I can't really explain it... But when driving I feel like something is rubbing with every rotation of something (could be rotor or something, or something within the engine). Like with every rotation of X (X being whatever the problem is) I can feel/hear it. I dont think it's my brakes since I just had those checked out at the dealership. But it feels like a sort of "slide". Ex: if you take your right hand PALM and keep it still, and take your left hand PALM and rotate it in a circle... every rotation of your left hand palm you slide it against your right hand.
(I think that makes sense...)

This seems to only be noticeable at low speeds (up to around 30mph or so)

 

Check your tires for something stuck in them. I had a similar sound coming from the front, reminded me of a bad wheel bearing sound. Blew my mind when I found a screw stuck in the tire. Removed it, it was a short one, so it didn't puncture it, and the sound disappeared. Just a thought.

 

If the dealership said they were fine than they must be all right... hahahahahaha!
Sorry, sorry, just kind of struck me in the funny bone.

Maybe a slipped belt in the tire? I would rotate the tires and see if the sound/vibration moves or changes. This you can do by yourself provided you have a jackstand and jack; if you don't then shame, shame on you.

 

Driveshaft???

 

I'll listen to it in a couple hours when I have my next class. But I think that I cannot hear it from a certain tire...

 

If the dealership says it, it must be the truth.
Is it still under warranty?
Were they just trying to get rid of you?
I would say check each wheel assembly by rotating
then one at a time by hand with the vehicle jacked up.
Could be warped front brake rotors.