Hello I am proud to be a part of this forum as I have gained valuable information over my short time here, Im super appreciative to all the posters that have shared what they know.
I have a 2009 ls460. When at highway speeds I can feel a shudder or something not balanced correctly. I thought maybe it would be the drive shaft imbalance however my tire shop told me the two rear wheels were bent (the car had been wrecked and I figure that’s when that occurred) I purchased two used rims on eBay and they balanced out fine and I thought problem solved the ride was a little smoother. Then I changed all front control arms (a few of the bushings were dry and cracked badly, going over bumps it was very noticeable) I purchased all beck arnely parts and brought it to my mechanic, he installed all 8 front control arms and aligned the car. The car is definitely smoother in the front end but now I have a very noticeable imbalance in the front end. You can feel a shudder in the steering wheel when getting up to speed and at 70-80 it’s most noticeable, to the point that you can see the steering wheel move slightly left to right back and forth quickly. I know that I need to take it back to my mechanic however I am looking for advice if I’m missing anything that hasnt been looked at. Or what I may be looking at next. I am mechanically inclined and know what things should look like or what may be wearing different. I just want my 460 to ride like a 460. Any help or advice is greatly appreciated. By the way the car has 95k miles on it

Looks like you’ve already got me beat, in regards to swapping bushings and tightening up the front end. I am chasing a 65-75 mph vibration as well, but have started leaning toward the fact that my tires may be the culprit. How do your brakes look? I’ve heard some have had an issue with replacement rotors being easily warped. As far as the tires are concerned, I plan on checking to see if I can find a shop that can Road Force Balance my tires and see if that helps. I’m not sure if they have been balanced that way at my local discount tire.

Thanks for the comment,
I changed the pads and rotors myself about 10k miles ago, they feel fine no bumping when stopping that I can feel. My tires are also pretty new, they have about 14000 miles on them. Let me know if you have your car road force balanced and if that fixes the problem.

Alright so I went back to my tire shop, paid to have them road force balanced and no difference, they said there was a slight variance that they adjusted and everything was fine. I got up to highway speeds and no difference in the shudder/vibration. I brought it back to my mechanic, he drove it (he said up to 75mph) and said no problem everything is fine. I brought it to another shop to get the alignment done and the tech advised I need to take it back to the shop that installed the control arms, he said everything looked correct and was tight but the caster on the passenger front was way forward and he was unable to adjust. The car also noticeably pulls to the right. I’m beginning to get frustrated as I have paid about $1500 to get the control arms replaced and ended up with a worse riding car then before. The shudder can be felt as low as 60mph but considerably worse at 80mph and even worse at 90mph, I can also hear and feel a very high frequency vibration in the steering wheel and gas pedal, floor board, almost as if there is metal on metal somewhere and transfering vibration to the car, I don’t know what I’m missing, and trying to prepare myself before I take it back yet again to my Indy mechanic. Any advice is greatly appreciated.

I switched from poor riding pirelli’s to Michelin’s.

I have Michelin’s on it, I’m sure at this point it is not the tires unfortunately as that would be an easy fix.

The damage was not extensive, it was on the front drivers side quarter, bumper, and hood damaged, it appears the bracket for the bumper on drivers side was replaced but noting else bent or changed. That is also my big concern, however the car didn’t ride like this until I got the work done on the control arms, and prior alignments showed to be fine, (I had it aligned when I got new tires, about 15000mi before the control arms replaced). How would I determine a chassis twist?

If memory serves me some auto body shops have frame straightening jigs. And in the systems memory is the relevant measuring points?

alright well as luck would have it I now have the dreaded brake lights on and message “immediately stop and contact dealer”. So I dropped the car off yesterday for inspection of the brakes, and imbalance and pull in the front end. Wish me luck as I cannot afford a huge bill from Lexus. As I’m thinking it’s likely the actuator how hard is that to get to and replace yourself?
I really cannot fork out 4K to have it fixed, I do plan to ask for assistance from Lexus as the brake actuator has never been replaced and the car has 97k mi on it, the extended service bulletin covered up to 100k but expired Dec 2017. I know most will say find an independent but I’m feeling like I don’t have confidence in my current independent who I have used for over 5yrs (precision align in Mckinney TX). If any of you are in the Dallas area what Indy shop do you recommend for working on these vehicles? Thanks for all the support and added knowledge, it’s much appreciated. And again wish me luck 😊.