Shaking even after balancing and alignment
 

I bought my Lexus used a couple of years ago - a 2008 ES350. After I had the tires rotated, the tires were loud and the car shook, even after the tires had been balanced and re-checked at least once. The shop couldn't find any issues with the car, so they rotated the tires back and it improved, but still wasn't as quiet and smooth as it was when I originally bought it. I went ahead and replaced all of the tires, and it was wonderfully quiet after that. I've now put about 10,000 miles on them so had them rotated. Immediately, the steering wheel started shaking at about 65 mph, so I had the wheels balanced, and it didn't change anything. I brought it back, they checked the balancing again, checked the steering, suspension, etc, and can find absolutely nothing wrong. I had them rotate the tires back the way they were and the steering wheel stopped shaking, but the passenger front seat does shake some and I can feel the whole car shaking a bit. I just had it aligned, because it was pulling left, and it didn't change anything with the shaking. It would seem that if the shaking shifts when the tires are rotated, it would have something to do with either my tires or wheels. But if it did it with both the old and new tires, it would seem to be the wheels. However, no one has noted a wobble when I've had the tires balanced. Is a bent or warped wheel the likely culprit? Suggestions?

Kindly check the engine seats; they probably worn and need replacement.

Check both of your motor mount.