Really bad vibration

Topic: Really bad vibration (Read 1900 times) previous topic - next topic

Really bad vibration

October 24, 2007, 11:20:09 PM

The other day I was driving my 88 tbird to work in stop and go traffic. At times I actually got up to about 20mph! All was going as it usually does then at one point when I was accelerating in 2nd gear it started having a vibration I never noticed before. You could feel it at low speeds. I merged on to the freeway and as I went faster it got worse. By the time I reached 65 the car was not drivable, it was shaking and vibrating so bad (the entire car). I had to slow down to below 60. As I was arriving at work I then noticed the drive shaft was rubbing on one of the lers. It wasn't doing that before. So I replaced the u joints. That made virtually no difference in the vibration. I then took it to a shop and they found all the rubber busings in the rear end "links" where rotten. So 673 bux later I had all new bushings. Guess what?, vibration is still there. I can't go above 65mph because the car is vibrating so badly it is not safe to drive. Shift stick is ready to jump out of the tranny at 65 it is vibrating back and forth so badly. I have very little vibration in the steering wheel. It was a turbo coupe but I put a v8 and tranny from a mustang in it 7 years ago. No real vibration till now. And that came on suddenly. It does not seem to vibrate if I just sit there and rev the motor. Ideas anyone??

Really bad vibration

Reply #1 – October 25, 2007, 08:41:02 AM

I had a very similar situation. Turns out my wheels/tires were out of balance. Something you might want to check into. I had little to no vibratin in the steering wheel, but the dash vibrated so bad, a couple of screws fell out. Got everything rebalanced and all was ok. :burnout:

Really bad vibration

Reply #2 – October 25, 2007, 10:59:57 AM

Check the bolts that hold the driveshaft to the rear-end. They tend to back out suddenly.

Also check your clutch movement. Might have eaten the pilot, throwout, or simply the whole clutch. Especially with the "shifter jarring".

Really bad vibration

Reply #3 – October 25, 2007, 01:15:57 PM

I had that as well.It was a tire that had the tread seperate on it.You can barely see it,but the tire was messed up.Check the tires and balancing.Tires first.

Really bad vibration

Reply #4 – October 25, 2007, 06:11:37 PM

if the driveshaft was rubbing on the ler i would think to check the motor/trans crossmember mounts

Really bad vibration

Reply #5 – October 25, 2007, 06:15:39 PM

Unless the lers were installed later my an idiot.Even still,that probably wouldn't make the car vibrate like that.

Really bad vibration

Reply #6 – October 26, 2007, 05:43:43 PM

Whats the verdict on this one,That bad of vibes that quick is got to be something noticable!!

Really bad vibration

Reply #7 – October 26, 2007, 06:01:20 PM

Just a thought. Since these cars have coils in the rear there's a centering link (I can't remember the correct term) that keeps the rear from moving from side to side.

What if it or it's mount is worn or broken? You'd possibly get the driveshaft rubbing on the lers. Vibration? Maybe!

Just thinking.

Really bad vibration

Reply #8 – October 28, 2007, 09:03:29 PM

it might be the drive shaft out of balence .most drive shafts have weights on them.

Really bad vibration

Reply #9 – November 05, 2007, 06:34:43 PM

Well so far I have rebalanced the tires, redid the bushings in the rear links, replaced the u-joints. Still have terrible vibration at 65+. Can a bad motor mount cause vibration at higher speeds? And now I have this tinkling noise, like sheet metal rubbing on something. I looked at the drive shaft but I did not find anything touching it. The "tinkling" sheet metal noise goes quiet at about 40mph. Weird! Any ideas? This noise showed up within minutes after the vibration started originally.

Really bad vibration

Reply #10 – November 05, 2007, 07:02:38 PM

Since you've done everything except checking the motor/trans mounts I vote that you do that next.

Just suppose the engine and tranny are moving about...side to side, up and down and the only stable thing you've got is the rear end. So, you accelerate, the engine torques up and to the right, the tranny tail shaft goes left, right, left, right and causes the driveshaft to make that "tinkle" sound on the exhaust. I really think ductape91's got it right.

While your down there check and see if the flexplate to torque converter bolts are tight, the exhaust hangers are good etc. etc.

Really bad vibration

Reply #11 – November 11, 2007, 09:23:27 AM

The TC driveshaft has a damper at the tranny end that will come apart and raise havoc. If you have this damper it's time to check it out. Most people remove them with no issues after they fail.