60 mph shake

[zamjohn]

This is certainly not a new topic however to me involves a solution to a common problem among Bonneville owners. I have had for a number of years the common problem of 60 mph shake or vibration on my 04 Bonne SE. From year to year the problem kept getting worse and I couldn't find the problem. The solution began when I had a blowout on my front driver's side tire last summer just north of Springfield MO at high speed. Had to buy a new tire and when I got home purchased another of the same for passenger front. No change! This spring I purchased new same tires to replace other 2 and whatayouknow, the vibration is completely gone. The tires are not top of the line only Hankook Optimo. I retained 2 of the old tires for spares as the tread was still decent for 100,000 KM. Upon examination, I discovered a significant number of flat spots on the old tires which is what I believe caused the vibration. Surely not a universal solution but it was for me.

[Luxrain]

i would keep a close eye on that myself. ive put brand new tires on my car about 2 times now (new snow tires and new summer tires) and after a while the vibration came back for me

[MKMike]

This spring I purchased new same tires to replace other 2 and whatayouknow, the vibration is completely gone. The tires are not top of the line only Hankook Optimo. I retained 2 of the old tires for spares as the tread was still decent for 100,000 KM. Upon examination, I discovered a significant number of flat spots on the old tires which is what I believe caused the vibration. Surely not a universal solution but it was for me.

Multiple flat spots typically indicate worn out rear shocks or severely out of balance tires.
If it's the shocks, it will happen again.

[zamjohn]

I have replaced the rear shocks twice in the course of driving it 100,000KM as well as rotate the tires. Never has been any bounce in the shocks or the struts up front so I am kind of puzzled how the flat spots appear. Out of balance would definetly be an issue. The car had new tires when I purchased it and no vibration. It took a couple of years for the vibes to start.

[redfury]

Could be bushings that are giving you a bit of a wiggle. How does the car handle when you shimmy the car left to right and back..does it track tight, or do you have a bit of sway...

[MKMike]

Wheel weights can get knocked off or loosen over time.
If a wheel weight falls off or is loose and moves to the wrong spot, it puts the wheel out of balance.

[sdxp787]

I had the seventy mph shake and it was the rear shocks... they were blown.

[zamjohn]

Haven't checked back on this topic in a while since I don't have this issue anymore. I replaced rear shocks in February of this year and the tires in late April of this year. Quick left & right shimmy gives very quick response with no sway. I do however note something in the last couple of months and that is driving from cold start gives me a little play in my steering but this disappears completely after 5-6 miles of driving(possibly a leaking seal). Nothing serious though.

[57j2olds]

I had the 70 mph shake. Replaced my stabilizer links bushings and got a front end alignment and now I can go to 75mph..lol...

It's so annoying.

[57j2olds]

I had the seventy mph shake and it was the rear shocks... they were blown.

Did the rear shocks cause the front to shake at high speeds?

[sdxp787]

I had the seventy mph shake and it was the rear shocks... they were blown.

Did the rear shocks cause the front to shake at high speeds?

It was very hard to determine where the shake was coming from. It felt like it was from the front, but it was the rear... but it would start shaking at 70 and stop at 75... I changed the shocks with KYB replacements and it went away.

[MKMike]

As a rule, a front end issue causes a shake felt in the steering wheel.
A rear end shake causes the vibrations to be felt in the seat.

57j2olds wheel weights often shift or fall off over the years.
Hitting a pothole can do it.
In addition, some tire shop employees either are lazy or clueless.
Rather than balancing the tire until the machine says zero weight is required, they only add weights after the first spin.
Proper wheel balance requires that weights be added and the tire re-spun on the balancer until zero additional weight is called for.

[57j2olds]

Can bad front sway bar bushings cause a vibration?

[MKMike]

IDK.
Here's one quote from this vibration thread
http://www.pontiacbonnevilleclub.com/fo ... 17296.html

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.

This thread may help