A clunk over bumps and potholes on a Kia K5 or Optima usually points to worn sway bar links, strut mounts, or control arm bushings.
Here’s what to check first — and when it stops being safe to drive.
Why the Front End Clunks Over Bumps
If your K5 or fourth-gen Optima knocks and clunks when you roll over potholes, speed bumps, or broken pavement, you're not imagining it — and you're definitely not alone. The front suspension is a chain of rubber bushings, ball joints, bearings, and fasteners, and every one of them has a job keeping metal away from metal. As the miles add up, a little play develops in one of those joints, and what was a cushioned thump becomes a sharp, hollow clunk you can feel through the floorboards. The trick is figuring out which component has gone loose, because a $25 part and a $400 part can sound almost identical from the driver's seat.
