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another 00+ owner with mysterious vibrations... brand new tires and balancing. its really bad from 70-80mph, 10 mph in either direction it tapers off, and 15-20mph in either direction its completely gone. I would expect it to be less going slower but surprisingly it gets better the faster I go also.

my rotors are SLIGHTLY warped but I wouldn't think that would cause this much vibration. with no one in the passenger seat, I can see it shaking around a lot.

i know there are a few who have not been able to solve this, but maybe i can be the lucky one

O.o

Please, don't curse me with the shakes!!!! Um, I'd look at the rotors, tie rod ends, bearings, CV shafts, pretty much the whole front end.

i dont shake!!

00Beast wrote:O.o

Please, don't curse me with the shakes!!!! Um, I'd look at the rotors, tie rod ends, bearings, CV shafts, pretty much the whole front end.

well thanks!

not what i wanted to hear!

Warped rotors was the cause of mine. Known that they are warped I would definitely start there... you gotta fix them either way.

Good luck with it.

I did it all. New CV axles finally cleared it up for me. One of the axles I couldn't tell was bad, but replaced it anyway, and that cleared it up. Good luck.

thanks for the input guys. i dont really have to replace the warped rotors now, they have been warped on all 3 bonnevilles, i usually just wait til i need new pads too.

interesting that that helped you though, i didnt think they would make much of a difference. i guess i will try that first.

Was this a problem before the new tires?

If the vibration came on with the new tires have them rebalanced. I would also have the tires rotated, If the vibration continues and has moved to a different part of the car you would know it is a bad tire.

If you can see the seat next to you shaking I'm gonna guess that one of the tires on that side is WAY out of balance/shape.

Just something to check that my step dad mentioned to me. Check the serial number of the tires you purchased. The last 2-4 digits are usually the manufacture date. You never know, but you could have gotten an old tire that was already falling apart inside from age. I would definately switch them front to back to see if the vibration moves. Thats how I determined most of my shaking was coming from a bent rim. My car still vibrates a little but its hardly noticeable now.

grandprix104 wrote:Just something to check that my step dad mentioned to me. Check the serial number of the tires you purchased. The last 2-4 digits are usually the manufacture date. You never know, but you could have gotten an old tire that was already falling apart inside from age. I would definately switch them front to back to see if the vibration moves. Thats how I determined most of my shaking was coming from a bent rim. My car still vibrates a little but its hardly noticeable now.

After the DOT the first two are the plant code the last 4 are always the month and year of manufacture. A tire doesnt have to be old to have a problem I replace brand new tires occasionally for customers who have gotten a bad tire.

ice buildup on the rim?

not any ice buildup that i can see. i took a fairly good look.

I plan on switching them front to back tonight, but my rims are slightly bent the tire shop told me that. they like to tell everyone that, in case it's causing a vibration and they don't want to get blamed for it. but they told me that before the vibration started. so i doubt that's it. even if it is, moving them to the back should tell me whether it is a wheel problem or not.

I have the same vibration problem...it appears around 72mph. When I hit 78-80 it goes away completely. Very weird.

I haven't started tearing into things to replace yet...but I have new pads and rotors, so I doubt it's that. It doesn't really bother me enough to spending big money replacing things that don't really need replaced.

*added to list

Thanks for adding this to the common problems list, especially since there has not yet been a common fix for it yet.

I, as with many others here, have had this problem for several years now with no common fix having any effect. The problem is exactly as described here above, happens around 69 to 73 MPH and fades away below or above that ... doesn't come back even way above that . I can only add with certainty that the speed band at which is starts/stops oscillating will vary depending on whether your driving into or with the wind, so I suspected for a while an aerodynamic issue, maybe a loosened wind dam (which perhaps won't oscilate anymore above 74MPH because it would get pressed back enough in place from air pressure at the higher speeds). Into the wind the ocsilation starts/stops in a lower speed band, and with the wind at your back it starts/stops at a higher speed band.

No one please take this the wrong way, and maybe its because I am so frustrated at not nailing this down by now, but please, please spare us the "It's got to be the: new tires/not getting a roadforce balancing/warped rotors/shocks/swaybar links/endlinks". I, along with may others have "been there done that", and I have replaced everything in the list in the last sentence and nearly everything under the car especially in the rear suspension. No effect whatsoever.

I suspect that those who have claimed that a "vibration" was fixed with certain noted solutions noted above likely fixed some other type of vibration or shake. I still welcome though suggestions from anyone who is positively 100% sure they fixed the exact problem described here: I'm desperate!

replaced everything with the exception of

- the rear trailing lower control arm bushings (can't find an aftermarket manufacturer of them)
- cv axles (as suggested above) but doubt the source of the oscilation is coming from the front.

Someone once noted that generally vibration felt in the steering are typically front-end issues and vibrations in the seats (which is what this sympom is) is typically coming from the back of the car.

Hopefully this thread will be visited by more than one lucky 2000+ owner confirming the same fix for this exact problem. Haven't seen that yet.

I am subscribing to this thread in hopes we will soon finally hear of a fix to this unfortunate problem, most unfortunate for me because it happens at the exact highway speed band I do a ton of driving at.

Cheers!

We had the left rear rotor out of wack and causing vibration only when we slowed down. I replaced both of them. We just recently after a strong rain, had a vibration in the front end. The vibration was coming from about a baseball size build up of mud on one of the front wheels. Just a good wash down took care of it.
Troy

I would rotate the tires and see if the major vibration moves. Tires can be a major issue...even when properly balanced. The truck had the worst vibration at 80...mirrors would start chattering, etc, new tires, completely stopped it.

It is one try..doesn't take much time, or if you can't do it, not much money. Its an imperfect art making a big chunk of rubber spin smoothly.

Thanks for the suggestion. I've rotated the tires a number of times. On the last rotation though it did seem once that the shimmey moved to the front and I thought AHA! Gotcha! Got the front tires put on the balancer again and was assured again that they couldn't be more perfectly balanced. Put them back and no front shimmey -- still seems like it's coming from the back again. My guess was that the front shimmey was something else like maybe ice/snow build up. Problem is that the 'hwy shimmey' doesn't always present itself 100% of the time which makes this all so much more mysterious and difficult to nail down.

Question: IF the problem really does relate to out-of-balanced tires or even perhaps a separated belt, wouldn't the vibration occur at various speeds. The thing is ... that this dang issue happens in only in one speed band. IF it was a tire balance/or belt issue, I would expect to find vibration symptoms at a number of speeds bands and certainly at much, much higher speeds which I have tested.

Thoughts?

New tires, numerous road force and on-car balances, new tie-rod ends and new right axle did nothing for me. I've been putting up with this for 3 years. I love the car, just not on the highway.

...and as one person mentioned, the level of severity seems to vary wildly from day-to-day. Very odd. Very interested to follow this thread.

I just switched my front tires to the back, there is about 3" of snow on the ground and still coming down, so no way will i be able to get up to 75 or so today, but tomorrow i will let you guys know if anything changed. next on my list is warped rotors (i doubt they could be causing this much vibration, but they need to be done anyways)