i was driving and all of a sudden i notice a wierd vibration under my feet. it vibrates, pauses, vibrates, pauses, and so on and so on. dont know what it is. doenst happen in park or any thing else but drive and the first 3 gears. i have an automatic if it matters. no pony package or ne thing
I have the same vibrating proble on a convertible 07 I just bought brand new.. I noticed this vibration that I figured had to come from the exhaust loose bracket and I brought it to the attention of the salesman. I bought the car and was told that this was a bracket issue. The dealer even gave me a copy of a Mustang service bulliten that requires the dealer to remove a particular bracket. However the rattle did not disappear. I took the car back two days late (yesterday) and today was asked to pick it up with an excuse that the dealer called the hotline.. that they are aware of the problem but have no solution.. that I would have to wait and will be contacted (which I do not trust) when a solution is found by Ford.. Another guess I have is a defective U-joint connectinf the Gearbox to the rear axle as if this out of alignment it would rattle at certain speeds..
I do not know what to do next.. a bummer since they will not take the car back..
Any particular speed that it occurs? Out of balance tires can do some weird things, misalignment also can cause freaky things to happen. Just mentioning some other possible causes.
I have the same rattling issue. The TSB's state that it's caused by the brackets that hold onto the exhaust hangers. Specifically, the ones on the transmission crossmember. If you can get under the car, you'll see the two brackets, one for the driver's side and one for the passenger side.
These brackets have a rubber isolator that the exhaust hanger mounts to. The rubber absorbs the vibration. If the rubber part becomes distorted (example: the exhaust hanger is pulling it too far down) the metal hanger can contact the mount and create the sound you hear.
I got under the car and looked at both exhaust mounts. The passenger side one was fine, but the driver's side rubber was sagging... So I tested it. You can test it by tapping the mount with a hammer. The damaged driver's side mount made a small vibration, like how I hear it when I'm driving. It was more subtle, but it was there. The undamaged passenger-side mount sounded solid (sounded NOTHING like the damage driver's side mount), meaning it's perfectly okay.
05-8-6 may not have anything to do with this, it just cover's rattle and doesn't give much info. 06-4-1 tells how to test for the rattle, as I described. It involves using bands to tighten the mounts, which is really a "band-aid"-type approach, and might be how otabish's dealer tried to fix the problem.
08-3-4 is relatively new and supercede's 06-4-1. It says to completely remove the mounts and bend the hangers out of the way. They were only there as a production line aid. Personally, I'm not going to take my car to the dealership to have this done, as I want to keep the brackets. I'm just going to cut off the exhaust hanger, so I still have the brackets on the tranny mount for when I get an aftermarket exhaust.
At the very least, you can test the mounts with a hammer. I hope this helps.
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2007 Vista Blue 4.0 V6 Mustang (Pony Package) JLT Intake + 93 octane BamaChips tune JBA single axle-back exhaust
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wierd vibration on my 07 - 
