Bad vibration under load, what is it?

[Killercanary]

I recently drove a '95 GT 5 speed coupe that has a NASTY vibration. The vibration is very pronounced under acceleration. Its there while not under throttle, but as soon as you give it some gas its vibrates much more violantly. I got under the car and with the car on jack stands and the ebrake on, I couldn't feel any slop in the U joint which was my first thought. I wanted to see if anyone else had any ideas. I did notice that the harmonic balancer needed replaced too since it was wobbling quite badly. The car has 130K miles and is 100% stock except for underdrive pulleys and a short throw shifter. The clutch feels likes its on its last leg as it engages clean at the very top and there is no adjustment left in the stock quadrant. Does anyone have any ideas as to could be the cause?

 

['94ChickStang]

as you mentioned, mine had those symptoms when the harmonic balancer was wobbling

 

[Zero_chance]

Definitely the balancer, especially if you can see it wobbling. Mine has the same symptoms. Im just too lazy to get it fixed and I work at a Ford dealer... though if I go with a Ford replacement itll still be on borrowed time from what I hear. In any case Im putting the Eclipse on the road this week so itll have to wait till spring.

 

[Methodical]

I had a vibration in the motor once that occurred when the RR nut came loose on the #8 cylinder intake valve.

 

[Zero_chance]

There really are a lot of different possibilities, but since he knows the dampener is bad, thats always a good place to start. Besides, blown dampener can lead to worst damage like bearings inside the motor, etc.

 

[earleys94gt]

+1 on the dampener.

 

['66 coupe]

I did notice that the harmonic balancer needed replaced too since it was wobbling quite badly.

Definately the problem if you can SEE it wobbling.
When mine went out, I had a vibration at around 1300 rpms. But you couldn't see any wobbling at all. The only way you could tell it was the balancer was by feeling the rubber coming out of the back.

But yea, if it's so bad that you can see it, I can only imagine how violent the shaking must be.

 

[toxicpelican]

another +1 for the balancer, i had to replace mine on the last stang, it didnt even look too bad, car vibrated badly tho, changed balancer. bingo.

 

[final5-0]

There really are a lot of different possibilities, but since he knows the dampener is bad, thats always a good place to start. Besides, blown dampener can lead to worst damage like bearings inside the motor, etc.

What he said

Grady

 

[The Green GT]

Probably the balancer.

But they always look like they are wobbling because of the grove in them. After I changed mine I freaked out because the new one looked like it was wobbling all over the place.

 

[Black95GTS]

Mine vibrated as my clutch was going out.

Does the car shake in neutral when you goose it or just when the transmission is in gear?

Adam

 

[5spd GT]

Once you are hitting the gas (which I assume you mean in gear and not neutral), something is going faster

Replace that balancer promptly.