got some weird vibrations, need help
got some weird vibrations, need help ive noticed since i buoght the car about a month ago, it has some pretty bad vibrations, usually at higher speeds, (highway driving 60-80) it will start this pulsing in and out vibration which feels like its coming from under the center console. i also notice sometimes when i take off with a little gas from a stop it will make a big clunking noise and then just free up and go....ive taken the driveshaft out and checked the u joints, both good, greased it, slapped it back in. i checked the tranny mount, looks great and feels great. any suggestions??? thanks in advance!
Teching In
Joined: Jul 2007
Posts: 17
Likes: 0
From: Louisiana
Dude, I'm having the same exact freakin problem... A pulsing vibration that started after changing TC, Gear and Trans...it got worse yesterday when I switched to a poly trans mount. My vibration will happen while under normal accel, then starts pulsing faster at about 45mph and at 50mph right as it almost becomes a steady vibration, it changes gear and the vibration changes.... I also pulled the driveshaft and my U-Joints were fine like yours, but I also checked the yolk and it did have some play in it, I have a video I'm about to post of that and get some opinions.... I hope you figure it out man, and please let me know if you figure it out, I'll do the same! Good Luck!
Check the nuts on the torque arm bolts that mount to the rear end. This will cause quite a bit of clunking if they are loose. Have you checked the balance of the rear wheels? Possible the balancing weights may have fallen off.
my wheels are perfectly balanced, just checked them, i havent checked the bolts yet tho, thanks for the advice.
kingsofstreet- yeah it sounds like we have the same problem, only problem is finding it now!
kingsofstreet- yeah it sounds like we have the same problem, only problem is finding it now!
If you have checked the tires for balance, the next thing I would suspect would be driveshaft balance or length. The bearings in the U joints if they are old. How about driveshaft pinion angle? Then on to a possible bent axle. Those are the easier things to check. If it still vibrates I would find someone with a stock 10 bolt and driveshaft in good condition and swap it out for testing purposes. Other then those things I would resort to pulling the tranny and balancing the clutch, if you have a 6 speed(which I dont believe you do).
On a side note I just corrected my vibrations with a new driveshaft from EPP. I swapped in my Currie 9 inch rear and my driveshaft was too short, causing the car to vibrate like crazy starting at about 45 mph. I'm talking vibrating to the point my *** went numb by 60 mph. New perfectly balanced driveshaft from bob and it is good up to at least 130 now. Vibration free finally.
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Teching In
Joined: Jul 2007
Posts: 17
Likes: 0
From: Louisiana
Okay, found my problem....... The pulsing of the vibration had me thinking it was in the driveline somewhere, but I'll be damned if it wasn't my exhuast vibrating against the drivers side floor.... I confirmed this by stuffing a quarter inch slat of wood between the pipe and the underbody.......... It still vibrated.... but very very little, then the piece of wood fell out, and it went back to doing it's vibe thing... So, that's one more thing to add to the list of funky *** vibrations causes. Just glad the wood fell out before I caught the car on fire.... 
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Gosh... vibrations really do suck. Not to hijack, but I'm having a horrible time with the same type of thing. I had a really bad clunk that sure sounded like the rear and the trans mount looked ok, so I put in a different 10-bolt and to me the rear feels better, but I still have the clunk, which I do think is the trans mount even though it looks fine. BUUUUUUT, now I have this horrid, horrid, vibration that just gets worse with speed and by 80 it actually feels unsafe to drive. It is especially bad during acceleration or turns. I did put in a different drive shaft, used factory aluminum one, since I have one of the unoptioned TAs w/o an aluminum DS. We also replaced the U-joints while down there. I tried turning the DS 180 degrees, but that didn't change it at all. Obviously I need to fix what i know is wrong and that's the trans mount (well pretty certain) and then maybe put the old DS back in. Anything else I should check out while under there? I find it really hard to believe that a DS makes a vibration THIS bad. The wheels certainly didn't unbalance when we swapped the rear so I think that's out as an option. One thing that was weird to me though was we had a really rough time getting this rear in and lined up properly and that's not usually the case in my experience so maybe I need to be looking for a bent axle or something. I guess this is one reason to not by used parts.....
mine too gets worse as my speed increases...and i take it out of OD and put it in D on the highway it starts pulsing really bad. i notice sometimes taking off from like a stopsign it feels like something is binding up and it feels as if its in the drivetrain becuase i can tell it restrics the movement of the car. could it be a bent driveshaft. once again...
tires and wheels, perfectly balanced.
u-joints are good, but car was rearended so could possibly be bent DS?
tires and wheels, perfectly balanced.
u-joints are good, but car was rearended so could possibly be bent DS?
I know what you mean about the vibration after 60mph, it very well could be your pinion angle is to far off, either a bent stock one or the wrong measurements on a adjustable one.
ive just recently got to the point where im tired of the vibrations and began replacing parts....new driveshaft,new u joints, still same vibration, moving on to the rearend now...bent axle?
Teching In
Joined: Aug 2009
Posts: 1
Likes: 0
From: hopewell NJ
i have a similar problem, though mine is more of an RPM issue, whenever i go through gears, acceleration is fine, but when i let off the gas it sounds like the rear end is about to come off, when i push the clutch in it goes away, its mainly in 2nd gear i feel it the most, checked the dshaft, ujoints everything seams fine
Registered User
Joined: Sep 2009
Posts: 3
Likes: 0
From: El Monte Ca.
I have the same problem after i installed my new transmission it gets a bad vibration around 2000 rpm and im still trying to figure out what it can be. i put it in neutral and it still vibrates at 2000 rpm..
Sorry to bring this back from the dead but im having a pulsing issue with my car where it will only start to pulsate around 55mph and progressively get worse the fast i go.
