I have the V6 and the vibration problem at 1500rpm's.

I was living with it until last week when i started to hear a 'rattle' in the dash during the vibration.

Took it to the dealer and they installed the damping kit as indicated in the TSB.

Well, it didnt fix the problem, only made it more tolerable.

So, today Im driving and the friggin rattle starts, (which sounds like glass vibrating). So i keep the car at 1500 which isnt hard to do since it practically lives there to isolate the rattle.

Couldnt find the rattle and didnt want to hear so i turned off the O/D to raise the rpms past 1500.

Guess what, the vibration went away when the rpm's sit at 1500.

If anyone else has the same issue can you see if turning the O/D off takes away the vibration....

 

Possibly??

 

Couple comments-

.71 OD on v6 auto gives 2100 driveshaft rpm @ 1500 engine rpm...suggest leaving OD off and running up to 2100 in 4th and see if it returns- if so its driveshaft related.

I read a while back about a v8 car with v6 crossmember (and/or tranny mount) having vibration, that was corrected by putting proper parts in. I would suggest if vibration returns at 2100 in 4th, take it back to dealer, explain why it appears driveline related, and see if they would consider physically confirming your car has correct crossmember/mount on tranny...Search in here or blueoval, or mustangforums, and find the thread about wrong parts from factory-it has happened(sorry I dont have a link or time to search- dialup here).
Ford did a very odd thing on the mustangs(to me anyway)- they have a front u-joint going to a carrierbearing with a c-v joint, and a c-v joint at the rear. If single u-joint has much angle at all, it WILL by nature of the thing impart velocity changes between input/output shafts twice per rev...wrong tranny tailshaft height relative carrier bearing could do such a thing. The 'weird' part to me is, I always *thought* a u-joint HAD to have some angle to it in order for the needle bearings to roll and prevent fretting corrosion- normally with a pair, the second one cancels out velocity changes from the first, so the only thing speeding up/slowing down twice a rev is the fairly lightweight center section(if end angles are equal and opposite anyway.) To me Fords design looks like it will either cause some amount of vibration if operating at an angle, or cause fretting of front needle bearings if running straight...

 

thanks for the info, i'll look into these suggestions.

 

<div class='quotetop'>QUOTE(lmmmmm @ March 10, 2006, 11:21 PM) Quoted post</div><div class='quotemain'>
I have the V6 and the vibration problem at 1500rpm's.

I was living with it until last week when i started to hear a 'rattle' in the dash during the vibration.

Took it to the dealer and they installed the damping kit as indicated in the TSB.

Well, it didnt fix the problem, only made it more tolerable.

So, today Im driving and the friggin rattle starts, (which sounds like glass vibrating). So i keep the car at 1500 which isnt hard to do since it practically lives there to isolate the rattle.

Couldnt find the rattle and didnt want to hear so i turned off the O/D to raise the rpms past 1500.

Guess what, the vibration went away when the rpm's sit at 1500.

If anyone else has the same issue can you see if turning the O/D off takes away the vibration....
[/b][/quote]
I never use OD in town, only the freeway.