2000 Wrangler Steering

Okay, here's a wierd one. I've got a 2000 Wrangler Sport with about 37,000 miles on it. Just last week, the steering wheel started pulsing when straightening the wheel out after a turn at low speeds. My mechanic looked it over and could not find anything wrong. The belt looks fine. There's enough power steering fluid. No leaks. He said it doesn't appear to be dangerous at all, just very annoying.

Any thoughts would be greatly appreciated.

Thank you!