WICKED vibration at 80+MPH
#1
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From: Ringoes/Flemington, New Jersey
WICKED vibration at 80+MPH
So I have been chasing down this bad drivetrain vibration forever. Im stumped. I just had all my wheels repainted and checked for out of round. one of them was bent bad so it was straightened and the guy said the rest were in spec. The driveshaft is fine as I have tried 2 different ones in my car, same vibration.
At around 80+ mph i can start to feel a small shimmy through the transmission.. when I put the clutch in or shift to neutral, it gets REALLY REALLY BAD. the funny thing is you can hardly feel it if you are in gear accelerating.
all my co workers at my shop keep telling me its the wheels, but the guy said he straightened them. Should I call BS on the guy that fixed my wheels and check my wheels again? or is there something else wrong with my car. I want to get my car dyno'd but im afraid ill get denied because of this vibration. thanks!
At around 80+ mph i can start to feel a small shimmy through the transmission.. when I put the clutch in or shift to neutral, it gets REALLY REALLY BAD. the funny thing is you can hardly feel it if you are in gear accelerating.
all my co workers at my shop keep telling me its the wheels, but the guy said he straightened them. Should I call BS on the guy that fixed my wheels and check my wheels again? or is there something else wrong with my car. I want to get my car dyno'd but im afraid ill get denied because of this vibration. thanks!
#4
Sounds to me more like something in your susp. is loose. I'd check all your bushings to make sure none of them are worn. I'd also get the wheels checked at a different location.
#5
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From: Ringoes/Flemington, New Jersey
i work at a dealership so i have the hunter balancing machine. I was just afraid to mount them cause of the new paint haha. ill check them in a week when I feel safe touching the wheels haha.
trans mount is fine. its a new poly one. ill check the U joints i had one replaced already
trans mount is fine. its a new poly one. ill check the U joints i had one replaced already
#7
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From: Decatur, TN (N-W of Athens)
I'm wanting to say it's pointing more toward the rear end, since you said that it gets worse when the clutch is disengaged, which takes load off the rear. It could be suspension related like SS mentioned, could also be inside the rear itself, or a wheel bearing. I'd check all the bearings and give the bushings a visual check.
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#8
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From: Ringoes/Flemington, New Jersey
thats what i was telling the guys at work like wtf if it was a wheel wouldn't be the same no matter what im doing to the car. I did do a clutch so i had the torque arm off... but im 99% sure i tightened those SOBs up. They were a pain in the dick to put back on
#9
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From: Decatur, TN (N-W of Athens)
You could take the bolts off the rear end for the TA and take them to a wire wheel to clean off the threads and maybe get new nuts as well. Tightening them back up will be much easier then. Otherwise... I'm saying this in ignorance and hope someone will chime in to correct me, but you could be a bit of antiseize on then to help them snug up. Now the reason I said what I did first, is because I'm not sure if it's a bad idea to put something like antiseize [AS] on a part that sees lots of vibration which could be slowly shook loose over time. Since AS does slightly work as a lubricant. Though we do put them on exhaust bolts/studs where the manifolds meet the y-pipe, and never have had them loosen up and leak.
#13
I wouldn't worry about it, they have worked themselves loose on a few people even after using lock-tite. you could also rig a safety wire up to it which is what some of those people ended up having to do. personally I have to tighten mine up usually once or twice a season.
#16
To me it doesn't sound like the wheels, pushing in the clutch shouldn't change the vibe if the wheels are out of balance. Are you still running the stamped torque arm or an aftermarket one? If its ajustable check your pinion angle.
I've always put a light layer of grease on my torque arm bolts and use a large 1/2 drive breaker bar to tighten the bolts, not saying its the right thing to do but I've never had mine come loose.
How many miles are on the Trans? If its high milage check the output shaft bushing (where your drive shaft slips into the trans) for wear, you can simply push up and down on the front of the drive shaft to see if there is any extra clearance in the bushing.
I've always put a light layer of grease on my torque arm bolts and use a large 1/2 drive breaker bar to tighten the bolts, not saying its the right thing to do but I've never had mine come loose.
How many miles are on the Trans? If its high milage check the output shaft bushing (where your drive shaft slips into the trans) for wear, you can simply push up and down on the front of the drive shaft to see if there is any extra clearance in the bushing.
#19
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From: Decatur, TN (N-W of Athens)
Pontta: The only reason I mentioned rear end (not assuming that was directed at me since you said wheels) was that I figured with no torque load being applied the axles could have a bit of play in them and start to vibrate. Until the load[torque] is reapplied and that slack/play is taken up. Maybe he's launched too hard a few times >_> Not that ANY of us beat on our cars
#20
i work at a dealership so i have the hunter balancing machine. I was just afraid to mount them cause of the new paint haha. ill check them in a week when I feel safe touching the wheels haha.
trans mount is fine. its a new poly one. ill check the U joints i had one replaced already
trans mount is fine. its a new poly one. ill check the U joints i had one replaced already