Sway bar end links clunk when hitting turns and bumps

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 IS350. It sounds like the end links are either improperly seated or mismatched for the F Sport sway bar. Even if you've added washers to minimize the space, if the end links aren't fully snug, it can cause clunking when the suspension moves. You might want to double-check that the end links are the correct length and specification for the F Sport bar. They'll allow movement under load if they're too short or long or if the mounting points aren't aligned correctly. Using a torque wrench to ensure the end links are tightened to factory specifications is key. Inspect the bushings, as worn or misaligned ones could also contribute to the noise. 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!