at least the cops aren't giving me citations.

anyway, i took my car in and besides making me pay 40 bucks to drive my car on the freeway, the mechanic told me that he was absolutely sure it was either the fly wheel or the clutch and i figured that it's the clutch because the vibration come even when the car is out of gear on the freeway. what do you all think? out of balance clutch?

Taking the car out of gear on the highway doesn't do anything. The driveshaft and rear axle are still turning all the driveline components, they just aren't coupled to the engine anymore. If the clutch is pushed in and the engine is allowed to return to idle, and the vibration goes away then whatever is out of balance is from the flywheel forward. If it stays then its from the clutch disc backwards. If the clutch is pushed in AND the tranny is put into neutral and the vibration goes away then you should be able to eliminate the clutch as well, since the input shaft will be disconnected from the driveline.

So it sounds like your vibration is coming from somewhere between the transmission output shaft and the rear wheels. Probably a U-joint or you have an out of balance, or bent wheel.

'Bad Vibrations' and Negative Waves are Felonys in California - :D

I agree with Mark C in that this is more likely a U-joint, Driveshaft or wheel issue.
But, I think we need more info on when the problem started (did you just replace the clutch?) or how you came to notice it (did it happen during a 7,000(+) RPM excursion of the throttle)?
If it is a Clutch that suddenly went out of balance then there will be other signs - like the clutch working "funny" all of a sudden (may have lost a spring, finger or ???) or the like. There are often balance wieghts applied to clutches and flywheels - but if they "let-go" you will usually hear it :eek: - and then feel the vibrations.

Post back with specifics if possible and maybe we can help narrow down your search for the 'Bad Rotational Carma'...

it started a long time ago, i've checked tires, alignment, u-joints, driveshaft, all of that, and nothing. i am fairly certain it came when i installed the current engine (little under a year ago i think), as i put a new flywheel and clutch in at that time and it started a little while after. it comes on at 3000 rpm in 4th- or around 70 mph. it's not the flywheel or the engine, because it does it only at road speed and not engine speed. clutch is my last guess, but from what mark said it may not be that, which kind of sucks considering everything else has been checked/fixed/replaced already.

Does it happen in 1st, 2nd, or 3rd gear at 3000 rpm? or does it only happen in 4th gear and 70 mph?

lil beast, here's my 2 cents...Always check the obvious first: Grease the zirks real well, grease the ujoints real well, check your front end alignment, THEN move on to paying someone to help you figure it out. Personally, I had a bad "shimmy" in my 69 coupe car. I rebuilt the front end, swapped out the ujoints and the problem is almost non existent now. my brother swears that the drive shaft should be balanced by a reputable shop... I hope that this helps and good luck (Those vibes can drive ya nuts :rolleyes: )

Dano graemlins/beers.gif

I had a vibration in mine for years. Not a bad one, but annoying. Started right around 60 MPH and disappeared around 80. Needless to say most of my highway time was spent in the vibration zone. Had tires balanced, U-joints replaced, checked engine and transmission alignment (TH350), swapped wheels front to back, etc. About 3 years ago I bought a spare set of 14x7 rally wheels and repro Polyglas tires to use at local shows. First time out on the new tires and rims the vibration was completely gone. I have to assume one of my original wheels is bent or out of round enough to cause a vibration. The originals with my Radial T/A's are still sitting in my tool house. One day I'll check the runout on them to see which one it is.