What is causing vibration in rear that coincides with rear axle rotation?

Hi, my name is Devin. I am an auto repair expert with the Car Genius team here at RepairPal. I’m sorry to hear you're having trouble with your LS430. Vibration in the rear that matches axle rotation could be due to several possibilities. A common cause is worn or damaged universal joints (U-joints) or driveshaft components, which can cause a rhythmic vibration at certain speeds. Since the car has high mileage, the rear differential bearings could also be a factor, as worn bearings often create vibration, especially under load. Additionally, an out-of-balance or bent wheel could also cause vibrations in sync with wheel rotation, so inspecting for any issues with wheel balance and alignment would be wise. If you need more advice, have any other questions about your vehicle, or would like to get connected to a RepairPal Certified shop near you, we have you covered. Give us a call at 877-913-1554, and we will happily help you out!