30 and 60mph vibration... |
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30 and 60mph vibration... |
MikeM |
Aug 10 2011, 12:44 PM
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#1
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Hi guys..I've posted about this before but still haven't cured it.
I have a vibration/shimmy at 30 mph and 60 mph. Seems to be the whole car that shimmies as opposed to just the steering wheel. I have balanced several times, switched wheels front to back many times, and recently tried a friend's wheels with brand new tires with always exactly the same vibration. I have adjusted wheel bearings, tightened and loosened them, same problem. There is NO play in the ball joints or tie rods,I've had the car aligned and I've had wheels repaired. What should I be looking at in the back of the car? Seems likely that something is wrong back there. I don't really want to throw a bunch of money at replacing parts unless I know it will fix it. BTW...car is a 74 2.0 liter. Any suggestions appreciated.... Mike |
SirAndy |
Aug 10 2011, 12:50 PM
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#2
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Resident German Group: Admin Posts: 41,651 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
What should I be looking at in the back of the car? - Trailing arm bushings or ovaled mounting hole. - Cracked suspension console. Jack up the rear and see if there's any side-play in your trailing arms ... (IMG:style_emoticons/default/shades.gif) |
MikeM |
Aug 10 2011, 12:55 PM
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#3
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Thanks Sir Andy...I'm not sure how to check side play in the trailing arms....
Mike |
r_towle |
Aug 10 2011, 01:19 PM
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#4
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Custom Member Group: Members Posts: 24,576 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
jack up the rear so that the trailing arm is hanging free and grab the wheel and shake is in every direction.
Rich |
MikeM |
Aug 10 2011, 01:28 PM
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#5
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Thanks Rich...
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Ian Stott |
Aug 10 2011, 02:12 PM
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#6
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Senior Member Group: Members Posts: 907 Joined: 28-January 08 From: Moncton/Canada Member No.: 8,635 Region Association: Canada |
I had a slight vibration, tires were balanced right to zero not just in the green on the balance machine and my rims are straight and true, got the concentric centering rings from Chris Foley and problem was solved. If all of the above posts/suggestions check out OK maybe they would help.
Ian Stott Moncton Canada |
underthetire |
Aug 10 2011, 02:29 PM
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#7
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914 Guru Group: Members Posts: 5,062 Joined: 7-October 08 From: Brentwood Member No.: 9,623 Region Association: Northern California |
Check your CV's. Those will cause it if coming loose.
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MikeM |
Aug 10 2011, 02:35 PM
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#8
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Checked CV's...all are super tight. Thanks.
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MikeM |
Aug 10 2011, 02:41 PM
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#9
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Does anyone know the proper size for the rear hub centering rings for Mahle wheels? I'm going to try to find them locally...Chris Foley is a loooong way from me.
Mike |
r_towle |
Aug 10 2011, 02:56 PM
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#10
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Custom Member Group: Members Posts: 24,576 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
get a set of calipers and measure the hole in the wheel, and the diameter of the hub...that should show you the difference.
I believe that Foley is the only one who makes them and keeps them in stock... Go to a high end wheel shop...one that has alot of bling wheels. They know where to get these things. rich |
r_towle |
Aug 10 2011, 02:57 PM
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#11
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Custom Member Group: Members Posts: 24,576 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
have you ever had a four wheel alignment?
Rich |
MikeM |
Aug 10 2011, 03:03 PM
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#12
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Rich...yes, I had it aligned by a reputable guy. He did a nice job, the car is straight and true. BTW, I checked the trailing arms...nice and tight with no play.
Not sure what else to do at this point. I have tried other wheels with the same result but I guess that doesn't completely rule out the need for hub centering rings... Mike |
Drums66 |
Aug 10 2011, 04:48 PM
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#13
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914 Rudiments Group: Members Posts: 5,321 Joined: 15-January 03 From: Coronado,Cali Member No.: 151 Region Association: Southwest Region |
.....Are lug nuts torqued?.........say what? (IMG:style_emoticons/default/poke.gif)
(IMG:style_emoticons/default/bye1.gif) |
IronHillRestorations |
Aug 10 2011, 06:01 PM
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#14
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I. I. R. C. Group: Members Posts: 6,719 Joined: 18-March 03 From: West TN Member No.: 439 Region Association: None |
Has any of the tires been plugged?
Wheels/tires balanced on the car? Venting clearance on rear calipers? Adjusted slack in front wheel bearings? Rear wheel bearings? Shocks? Rotors? |
Mike Bellis |
Aug 10 2011, 06:16 PM
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#15
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Resident Electrician Group: Members Posts: 8,345 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None |
If it happens at 30 & 60mph, that is harmonics from the wheels. Get the concentric rings or balance all 4 wheels.
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jmill |
Aug 10 2011, 06:19 PM
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#16
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
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jk76.914 |
Aug 10 2011, 07:07 PM
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#17
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Senior Member Group: Members Posts: 809 Joined: 12-April 05 From: Massachusetts Member No.: 3,925 Region Association: North East States |
Mine was doing something kinda similar. It was pretty good when I started out, but as the suspension warmed up, a similar shimmy started. Mine was in the front, at about 70 mph, but curiously the steering wheel didn't shimmy, only the body. In my case, the strut insert was shot. I figure that maybe as the shock warmed up, what little damping it had left it as the oil thinned. Then it was susceptible to minor imbalances that normally would have been damped out.
Maybe no connection, but thought I'd throw it in. |
MikeM |
Aug 10 2011, 07:27 PM
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#18
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Guys....thanks for all the suggestions. I'll try to answer some of the questions that have come up.
I must admit, I don't know what venting clearance on calipers is... On car balance is something I have not done. There is a shop in town that used to do that so I'll call them. The shimmy is not rpm dependant, it is speed dependant. I can feel it around 30 mph and then I can really feel it at 60mph. I have had the wheels balanced several times, but have not purchased the hub centric rings from Tangerine Racing. Thanks, and keep it coming!!! Mike |
MikeM |
Aug 11 2011, 04:21 PM
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#19
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Hi all...I have ordered the hub centering rings from Chris Foley,who is a super nice guy BTW, and I'll report back.
Cheers, Mike |
76-914 |
Aug 11 2011, 07:24 PM
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#20
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Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,504 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California |
I chased this same thing for over a year. One place even trued the tires. I was sure the ball joints and tie rods were fine. I was wrong. After rebuilding the front end it was perfect. I was relying on my front end experience with heavier cars. Mistake.
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