The steering wheel has a controlled wobble. It gets worse under hard acceleration. It still wobbles while cruising at a fixed speed. Consequently the whole car has a very light vibration. The wobble disappears under deceleration. I'd love any insight into the cause of this.

 

Axles

 

I second this. It is usually the culprit.

 

Axles or bad tires

 

Try tightening down the steering wheel.

 

My TL does the same. Also wanders slightly at high speeds and vibrates over 90. Curious how this turns out.

 

I'll second this !
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