highway death shake

[happygoluckynic]

I am dealing with is a pretty bad shake like you are all describing. Mine didn't start till around 150,000 miles though. New tires, rotors, brakes, rear shocks, motor mounts and still just shaking myself down the highway. It starts at about 45 and varies intensity, but is worst between 60-80. My nex stop is the wheels to make sure they are all true. How do I check the CV as others have mentioned, and I am with golfyeti, any one with link to diagram where body mounts are would be great. That sound logical to me as well. Any thoughts on what to check next? it is driving me crazy! My wife just doesn't get why it bugs me that bad. When you at one time could go 90 with out even realizing it....then even a little shake gets to you.

[hmmthatguy]

hey i have the same problem my 2000 shakes reallly bad but starts at 45 and stops at 60 and really does it going up hills and sometimes cuases it to throw tranny codes some one told me my torque converter is going and that that was what was causing the shake ...but how dopyou replace that?? they said it will only be a matter of time until it goes and when does that will be the death of my transmission

[golfyeti]

hmmthatguy

check your front trans/motor mount. They commonly fail on the 2000 +. If it is bad it could be causing the "jerking" or "bucking" that you describe climbing an incline. If so, what actually occuring is low-torque "engine rocking" at on a mushy front mount.

happygolucky:

Update: I tighened body mount bolts and although it completely eliminated both the rattles and clunking noises in the rear it caused no real improvement on my 65-70 MPH shimmy.

My next focus is front control arm bushings. My mechanic mentioned the front right control arm appeared loose at the control arm bushings. Wish me luck.

Will report back.

[happygoluckynic]

hmmthatguy,

Thank you so much for the update. I haven't had time to have any more work done on mine yet but I will soon. I swear it is getting worse daily and feel like I am going to shimmy right off the road. Look forward to reading your report back on this.

happygoluckynic

[enslow]

it was just aligned, the balancing was done a few months ago, but it had the problem a few months ago. i have replaced the rack, tie rod ends, iss, left cv shaft, and checked everything for tightness. ive rotated tires around to no avail. it almost seems like it doesnt do it all the time or at least not as bad and for no ryme or reason it gets better and worse. i was thinking maybe tires out of round but they are wearing just fine. i was also thinking struts, but then again they're not leaking and the tires are wearing fine and show no excessive bounce. my only other question was about the lower control arm tsb which i dont know if its ever been done. how do i tell?

Don't just assume that because the balancing was done that you don't still have a balancing problem. I had a shake at about 90 km/h just after I switched to my winter tires last fall. The tires were brand new that I got with the car the previous spring. It turned out that the balancing was out on all 4 tires. Rebalancing corrected the shake.

Do you have a friend you can swap tires/wheels with to confirm whether it's tire or suspension?

[alexcoqui]

I have a theory that the problem is internal. Because I too had the 60 mph vibration, the day I installed the intense PCM it moved the vibration to 50 mph. So I'm guessing that the problem is inside the transmitio. I'm having it rplaced soon, & if I see improvement or change, then Ill post it here.

[golfyeti]

I have a theory that the problem is internal. Because I too had the 60 mph vibration, the day I installed the intense PCM it moved the vibration to 50 mph. So I'm guessing that the problem is inside the transmitio. I'm having it rplaced soon, & if I see improvement or change, then Ill post it here.

Alex, if the problem was transmission related then you wouldn't get the shimmy after placing the car in neutral at 80 MPH and then coasting into the shimmy speed zone. See my previous post above. That's why I know the 65-70 MPH Shimmy is not drive train related.

I know that I now need to replace a front lower control arm (right) and a hub (left). Will order parts and will report back.

[myfirstbonnie]

Not necessarily, even though you are in neutral and coasting, there is still rotating parts within the transmission including the drive axles.

[golfyeti]

Not necessarily, even though you are in neutral and coasting, there is still rotating parts within the transmission including the drive axles.

do you mean CV joints?
Despite knowing little about them it sounds like a possible culprit.

[enslow]

From my service manual:

Shimmy, Shake, or Vibration:
-tire and wheel out of balance
-tie rod ends
-lower ball joints
-suspension bushings
-lateral or radial tire and/or wheel runout
-blister/bump on tire
-brake components out of balance
-weak strut
-drive axle

Do you have the ability to swap wheels with a friend? That would eliminate the tire/wheel balancing. I'm actually still not convinced that you're tires/wheels are properly balanced, even though you said you had them done. Mine had been poorly balanced the first time.

Also from my service manual:

-Vibration at highway speeds (drive axle)
-out of balance front wheels or tires
-out of round front tires
-worn CV joint
-Binding or tight joint


Clunk when accelerating from coasting? This would be another sign of a worn CV joint.

[carl]

Last weekend I again replaced the cv axles (one was leaking really bad again) and I threw in some cheap wheel bearings from ebay. Both axles (warranty) and both bearings totaled $80 plus some anti-seize and red loctite. Anyway it gave me a chance to look at other things and verify the torqing on the ball joints which I couldn't get accurately enough last time around. I found the passenger side inner tie rod was crap (Moog life-time warranty btw). When I popped it out of the knunkle and lifted it up, it flopped down like it had no ball tension at all.

And so garbage were the axles (leaking Cardone rebuilds) and garbage was the Moog inner tie rod passenger side. Is there any QC anymore?

Anyhow the repeat repair did cure my low speed wobble. Now to see how long the parts last .

As for the highspeed wobble in this thread, I would look into the fixes for vehicles that exhibit it the most...like jeeps. Although they have different parts they can give you some ideas of the cures and can translate the same steering functions to any vehicle. Now I think the primary causes still will route to end links/rods, bushings, mounts and stabilizer links within the steering components only.

[happygoluckynic]

carl,

you really think it is steering components only that are causing all this trouble? With my car it is a WHOLE car shake. That is why I have assumed it had to be something worse that the front tie rod ends that I have known were bad for a year now. But every shop has told me that would not be the cause of my shake. I am a little confused.......help me understand why the difference of opinion please.

[myfirstbonnie]

The best thing to do is to take both wheels off the front and put it on stands and inspect everything, tie rods (inner and outer), ball joints, axles, wheel bearings, sway bar end links, all bushings etc. Then do the same for the rear. Everything should be nice and tight with little play. It might not be one single component, but a couple being faulty or weak will amplify the effect.

[carl]

I am going by with what the majority of fixes happened to end up being for jeeps ( for which whole body wobble is a very common issue)... but of course it could end up being something different.
And don't go by my or anyone else's opinions no one can say for sure.

I will give you one thing that is absolute certain: I agree with MFB above...eliminate the front end by checking and replacing all the suspect components. Once you give the front end the clean bill of health, then you can move out from there. Start with the easiest pathways to verify and they will eventually lead you to the root cause. But leave no open ends... if its bad replace it and eliminate that piece of the puzzle so you will not have to backtrack.

[santacarl]

Wow...I thought it was just me....until I found this thread.

I've replaced the rack.....tie rod ends....had the tranny rebuilt.....

A while back I thought it was the tires....when I bought a whole new set....the same shimmy was there.....starts about 68 and is worse at 72 MPH....

I'm thinking with all these posts being the same or so similar that this is some sort of design issue....but I've found with Pontiac in the past that they will never acknowledge a design flaw electing instead to let the customer foot the bill for repairs......and I speak from experience...rack and tie rods at 40K....all 4 lift motors/actuators prior to 75K...... And I won't even go into the radio, which picks up ignition noise on the lower FM bands, which, BTW I was told, after review by GM engineers, was normal operation for this unit.....Bwhhaaaa.

[HurstGN]

When you do the balancing, see if you can find a shop that can do a road-force balance. My car always had a little shake, but it wasn't bad enough to really worry about. This latest set of tires, I decided to try the road-force balance. It was a little more $, but the shake is pretty much gone. Sometimes I may feel it a little, other times it's not at all.

In my experience, the road-force balance may be $ well spent in eliminating some of the variables here.

[carl]

Well in ANY case don't sit back and let it kick your butt.
If it were my vehicle I can't stop until its done... OEM engineering flaws or not, they are not gods by far!

Many a-time OEM designs have to be modified because they just don't cut it...in fact, thats how the aftermarket performance industry was born. Subframes, mounts, whatever... keep digging and eliminating until problem solved.

[gmman]

my experience: if i work at it long enough buying michelins and rebalancing has always worked for me. it can be a pain but i can't stand any shake. i even bought four tires and rims that looked pristine off an insurance salvage bonnie and kept swapping them into my originals until i found a combination that has no shake.

this doen not mean that there is not a design problem with the bonnie's structure or suspension set up. it just means i have found a combination of tires and rims that compensate.

[golfyeti]

Several regular balancings and then a recent road-force balancing did nothing for my 65-72 MPH shimmy shake. It shouldn't be long before I replace front lower control arms and tie rods. Perhaps worn bushings on them could be allowing just enough play to cause the shimmy in a certain resistance zone.

The only additional observation that I have is that the "speed range" shifts depending on headwind or tailwind. The shimmy occurs in lower range in a headwind and in a higher range with a tailwind... which I read as: "a certain level of wind resistance on the front of the car is required, or perhaps surronding air turbulance".

Pie in the shy ideas from me are that either the front wind dam and/or maybe the wheel well are bad designs (or been weakened or damaged) causing turbulance under the car or that the "coke bottle" body design causes odd turbulance in that speed range.

Not sure if that necessarily points to any new ideas or rules out much ,... but this is what I have consistently observered, again, with drivetrain engaged and not so that should rule out a few things.

Note: recent references here to "wobbles" at lower speed or on turns is not the same issue in my opinion as the very distinct whole-car shimmy that so many 2OOO+ Bonneville owners have described as "an unrelenting whole-car shimmy only in the 65-73 MPH range and no other range".

[jhudspe2]

has anyone gotten any more information on this problem, i just got my car back from the shop and i didnt notice it before but now im gettting the shimmy.. i had my rack and pinion replaced but i think they took a used part and replaced it (through a aftermarket warranty) maybe its the rank and pinion going bad again i dunno but im pretty mad im hoping i can have something to take to the dealer as far as an argument is concerned so they know what to look for..