I was doing some last minute mothers day shopping early this morning at Walmart and on the way back i think i broke something.
I was at a stop light and i accelerated kind of hard (nothing crazy) just picking up speed in a fun sort of way. I hit about 3K rpms (still in 1st) and was about to shift to second and i heard some strange noise from under the car and the whole car started vibrating. I was thinking rearend or driveline but i put it in neutral and it stopped shaking. In neutral i revd it and the vibration is still there. There is no noise coming from anywhere. I was able to drive the rest of the way home, just with a vibration/shaking. Its a real constant vibration that gets more intense as i rev. It doesnt shake the whole car, its just like driving over those grooves in construction areas.

Can anyone throw some possibilities as to what may have happened?
Its 4speed Saginaw, 402BB, 3.08 rearend

My only thoughts would be harmonic balancer slipped, broke,sheared a key,or flywheel-pressure plate damaged or loose. If you see no damage to those items try removing all the drive belts to the accessories. Good luck let us know what you find.

Sounds like someting in the clutch/pressure plate broke.

engine has had a wierd sound coming from it since the last rebuild and now this... going to pull the motor. Sheesh... will i ever end??!! This will be the third time in a year. damn.
What could have broke in the pressure plate area? Is there anything that oculd have broke in the trans that would cause a subtle vibration when reving the motor?

what about the mounts trans,engine.if it's jumping around that would definety be some vibration.also check trans to eng bolts.does it vibrate not moving?possible u joint?

I would sure do some checking before pulling the engine.

i made it home and i parked. I put it in neutral and revd it while not moving and the vibration is still there. it is not a real violent vibration but its noitceably uncomfortable.

...oh yeah, I cant feel the vibration when idling. So, i think its nothing to do with driveline/rearend as it doesnt seem to matter if i am moving or not.

Are you sure it's a vibration and not a miss??

Cam

I had a clutch plate center splined hub come loose from the "Marcel" pad deal on my junk 301 once years ago. (I think that's what the wavy thing that helps absorb the shock, shifting gears.)...

Anyway a couple of springs in it were loose b/c some rivets came unglued...

It was my car's original clutch plate..

Otherwise, don't know but I will say, I figure your Sag. tranny won't last very long if your car hooks...

pdq67

It definately hooked up when i accelerated! Tires didnt slip at all. Thats why i think it could be the sagin' Saginaw. Could something break in there that causes a serious vibration? There is no noise coming from anywhere, just seems like something is off balanced??