Driveshaft Balance???
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Driveshaft Balance???
I drive alittle faster than I should but I have a vibration at 83 MPH + in an almost stock 82 CFI. I had the tires balanced on the mag setting and I even tried in the regular setting with placing the wheel weights towards the center of the rim on the inside. Both times I had vibs at the same speed. I don't want wheel weights on the outside of my rims if I don't have too! So I'm wondering if it could be my driveshaft or halfshafts? Have any of you had a shaft out of balanced?
Race Director
Joined: Nov 1999
Posts: 10,643
Likes: 8
From: Foxfield CO 1970 Convertible
Driveshafts can be unbalanced or it could be some misalignment due to worn U-Joints.. Is there some crud on the shaft? It could also be the tires.
If it were me, I'd try rotating the tires or putting both front tires on the rear and rears on the front. If the vibration changes to a different speed, it might be the tires. If it's at 83 again, it could be related to the shaft. Jack it up on some blocks and check everything under there for looseness.
If it were me, I'd try rotating the tires or putting both front tires on the rear and rears on the front. If the vibration changes to a different speed, it might be the tires. If it's at 83 again, it could be related to the shaft. Jack it up on some blocks and check everything under there for looseness.
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
I tried rotating with no luck. I should have added that it is sometimes worse than other times but its always after 83mph. I sometimes can change the vib alittle by giving or letting off the gas. Thanks
Melting Slicks
Joined: May 2006
Posts: 2,364
Likes: 103
From: Centerville Louisiana
First question did you do any work or mod's before it started or has it been there and your just trying to track it down. mine does the same I did a shaftbalance new joints new tires rims and wll drop a few more bucks before I find it I'm sure
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
No to the mods. I have original (99000mls)stock 82 rims,breaks and suspension with BF Goodrich 255/60-15. The vib has always been their sometimes worse than other times. Thats what I'm trying to avoid $$$$. It cost $8 to $10 a wheel to balance here in a BUBBA $hit shop. At the moment I am looking for a shop that can balance the wheel on the car(I heard of this style balancer) or a shop that has a real high speed performance balancer. What does your vette do?Also are you running steel rallys or aluminum rims?
Last edited by hugie82; Nov 15, 2007 at 09:03 AM.
Racer
Joined: May 2007
Posts: 306
Likes: 49
From: Florida
Hugie, would you describe the vibration as a low frequency vibe, like someone playing on a bongo drum? Or a high frequency vibe like someone doing a roll on a snare drum?
I have a high speed only (90mph+) high frequency vibe that is driving me nuts. Sounds similar to yours. I have new tires, u-jonts, shocks, and spring. So its not that stuff. Im afraid it may be bearings or a diff?
I have a high speed only (90mph+) high frequency vibe that is driving me nuts. Sounds similar to yours. I have new tires, u-jonts, shocks, and spring. So its not that stuff. Im afraid it may be bearings or a diff?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
It seems like no one calebrates their balancers anymore!!! When I worked in the buisness every morning that machine was calabrated. Anybody know of a good name of a high speed balancing machine? Also do you guys think its worth the effort to rotate the shaft 180? I know the trans was rebuild years ago but everything else looks original. Sorry for the long post, I'm trying to get all possiblities out there. THANKS
Last edited by hugie82; Nov 15, 2007 at 09:36 AM.
Racer
Joined: May 2007
Posts: 306
Likes: 49
From: Florida
Hi freq vibes are typically driveshafts, u-joints, and or engine or tranny mounts. Low freq vibes are typically wheels and tires out of round or balance.
So becausae you say its a high freq vibe, I would not think wheel tire balance, but drive line and mounts. To eliminate the drive line and mounts, try to make the vibe go away by putting the car in neutral. I know this sounds a bit dangerous to be going 90mph in neutral, but as the strain is off the drive train and the revs drop to idle, if the vibe is still there i would start thinking bearings. Wheel bearing or yoke bearing. This is where I am now, and there both expensive...
So becausae you say its a high freq vibe, I would not think wheel tire balance, but drive line and mounts. To eliminate the drive line and mounts, try to make the vibe go away by putting the car in neutral. I know this sounds a bit dangerous to be going 90mph in neutral, but as the strain is off the drive train and the revs drop to idle, if the vibe is still there i would start thinking bearings. Wheel bearing or yoke bearing. This is where I am now, and there both expensive...
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Hi freq vibes are typically driveshafts, u-joints, and or engine or tranny mounts. Low freq vibes are typically wheels and tires out of round or balance.
So becausae you say its a high freq vibe, I would not think wheel tire balance, but drive line and mounts. To eliminate the drive line and mounts, try to make the vibe go away by putting the car in neutral. I know this sounds a bit dangerous to be going 90mph in neutral, but as the strain is off the drive train and the revs drop to idle, if the vibe is still there i would start thinking bearings. Wheel bearing or yoke bearing. This is where I am now, and there both expensive...
So becausae you say its a high freq vibe, I would not think wheel tire balance, but drive line and mounts. To eliminate the drive line and mounts, try to make the vibe go away by putting the car in neutral. I know this sounds a bit dangerous to be going 90mph in neutral, but as the strain is off the drive train and the revs drop to idle, if the vibe is still there i would start thinking bearings. Wheel bearing or yoke bearing. This is where I am now, and there both expensive...
Yes try the neutral test.Then try a diff. gear so RPMs will be at a diif level.If you cant lock overdrive out or lockup with the shifter you should be able to do it a diff way.I think on my 80 you could unplug the wire from the MAP sensor and it wouldnt go into lockup.
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Here is my report. Took it up to 90mph pop it in nuetral and the vib was still there with a slight change in intensity. I'm pretty confident it is the balance of the wheels. I called a freind at the STS tire and he said their crappy machines are only good for a 70mph balance
and even worse on the mag setting (I knew that 
) So for my next expensive trick
is call up my BMW stealer and see what they use? Hopefully they will take care of me since we just picked up an X5 last month. Any other suggestions for a good balance? BMW going to rape me!!!
and even worse on the mag setting (I knew that ) So for my next expensive trick is call up my BMW stealer and see what they use? Hopefully they will take care of me since we just picked up an X5 last month. Any other suggestions for a good balance? BMW going to rape me!!!
Melting Slicks
Joined: May 2006
Posts: 2,364
Likes: 103
From: Centerville Louisiana
Croaker I feel your painNo to the mods. I have original (99000mls)stock 82 rims,breaks and suspension with BF Goodrich 255/60-15. The vib has always been their sometimes worse than other times. Thats what I'm trying to avoid $$$$. It cost $8 to $10 a wheel to balance here in a BUBBA $hit shop. At the moment I am looking for a shop that can balance the wheel on the car(I heard of this style balancer) or a shop that has a real high speed performance balancer. What does your vette do?
Also are you running steel rallys or aluminum rims?
No to the mods. I have original (99000mls)stock 82 rims,breaks and suspension with BF Goodrich 255/60-15. The vib has always been their sometimes worse than other times. Thats what I'm trying to avoid $$$$. It cost $8 to $10 a wheel to balance here in a BUBBA $hit shop. At the moment I am looking for a shop that can balance the wheel on the car(I heard of this style balancer) or a shop that has a real high speed performance balancer. What does your vette do?Also are you running steel rallys or aluminum rims?
Thread Starter
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
Did you have the tires balanced on a GSP9700 road force balancer? If not, you could have a harmonic vibration in the tire itself. www.gsp9700.com has a shop locater.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Melting Slicks
Joined: May 2006
Posts: 2,364
Likes: 103
From: Centerville Louisiana
It Is. One thing I'm gonna try one day is to try turning the drive shaft end for end it looks the same on both ends. Has anyone ever cured a vibe problem like this you always read about them but hardely ever hear of cures. Good luck hugie keep us posted
