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So many have had the steering wheel shake issue, but mine seems a bit different.

On the highway around 60 mph, I get a significant steering wheel shake that comes and goes roughly every 50 seconds like clockwork. At its peak it is shaking a ton, and at its low it's perfectly steady. It almost feels like something is going in and out of phase. My initial thinking was that I had mud caked into both of my front rims causing an imbalance, and slight differences in tire diameter may have caused them to be in and out of phase over time, but there was nothing there. I changed over to my summer wheels and the vibration is lessened significantly, but I can still feel it somewhat. I haven't been able to confirm if it's the same 50 second period, which is my next task.

At any rate, has anyone else had this type of cyclical shake issue? Since it comes and goes, it doesn't seem like a bad LCA or other suspension component to me. All of the suspension joints seem tight and there isn't excessive play in the steering wheel. I'm stumped, so curious what everyone else thinks.
 

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So many have had the steering wheel shake issue, but mine seems a bit different.

On the highway around 60 mph, I get a significant steering wheel shake that comes and goes roughly every 50 seconds like clockwork. At its peak it is shaking a ton, and at its low it's perfectly steady. It almost feels like something is going in and out of phase. My initial thinking was that I had mud caked into both of my front rims causing an imbalance, and slight differences in tire diameter may have caused them to be in and out of phase over time, but there was nothing there. I changed over to my summer wheels and the vibration is lessened significantly, but I can still feel it somewhat. I haven't been able to confirm if it's the same 50 second period, which is my next task.

At any rate, has anyone else had this type of cyclical shake issue? Since it comes and goes, it doesn't seem like a bad LCA or other suspension component to me. All of the suspension joints seem tight and there isn't excessive play in the steering wheel. I'm stumped, so curious what everyone else thinks.
Interesting. I have a similar issue, and I'm starting to think it's just a balance issue. Some times my car will be glass smooth, then others the steering wheel will shake enough to shake my arms. It seems to change as I go around curves/turns. As in the front wheels are lined up differently as they travel at different speeds through turns.

I think my TPMS are going out as well, so I'll have to get it to a shop and replace those and have them rebalanced and see what happens.
 

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My coworker and good friend had this issue on his G8, new wheels and tires still didn't solve it for him. Only when he did a CTSV brake upgrade did it completely go away.
Long story short it appears that out of balance front rotor/ rotors was the cause. I have heard of rust and crud building up on rotors in cold climates that have caused an out of balance condition, but we are here in sunny Arizona.
Heat warped rotors are usually only felt when applying the brakes. This felt and acted like an out of balance tire does.
Road force balancing would should fix it if you can find a shop that does it. Just don't rotate your tires afterwards.
 

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Discussion Starter #4
My coworker and good friend had this issue on his G8, new wheels and tires still didn't solve it for him. Only when he did a CTSV brake upgrade did it completely go away.
Long story short it appears that out of balance front rotor/ rotors was the cause. I have heard of rust and crud building up on rotors in cold climates that have caused an out of balance condition, but we are here in sunny Arizona.
Heat warped rotors are usually only felt when applying the brakes. This felt and acted like an out of balance tire does.
Road force balancing would should fix it if you can find a shop that does it. Just don't rotate your tires afterwards.
Well, you don't get much colder than we get in the winter. This could be the issue as I also have vibration sometimes at higher speeds when applying the brakes. Replacing the rotors was actually my next step in figuring this out since I can get a set of OEM-equivalents for reasonably cheap.
 

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Fifty-five years ago there was bubble balance off the car and spin balance on the car. Spin balance on the car took more experience to get it right. Spin balancing on the car was more expensive than bubble balancing. But it accounted for all of the rotating mass except for the wheel cover. Even then, heavy, out of balance wheel covers could still cause balance problems.

The off the car spin-balance machines do not require the experience required by the old spin balance on the car. But it doesn't account for out of balance drums or rotors.

Your thought that you have slightly out of balance rotating assemblies going into and out of phase with slight rolling circumference differences is most likely true.

I wish you success in squelching it.
 

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I have the very same exact issue with my G8, ebg8gt. The front brakes on my car are fairly new so I never really thought about it being a issue with the rotors. It does make sense though I suppose.

My next step was going to be changing the upper strut mounts and bearings. They are pretty noisy when turning the steering wheel back and forth.

I just picked up a full set of GM service manuals for our cars and I know it has over 70 pages devoted to just diagnosing shakes. I'll have to take a closer look and see what it says on the subject. It's a odd shake to diagnose, that's for sure.
 

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F1rehawk
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I also have mild steering wheel shake at highway speeds which seems to disappear and then reappear. I also believe the culprit to be the rotors. Any suspension part would most likely cause a constant shake. I'll see if it disappears when I upgrade my brakes sometimes next year. It's not a major issue for now.
 
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