2005 Jeep Wrangler Front End Shimmy at 55 mph

The front end of the Jeep, specifically focused on the right side of the front end, shimmys and bounces the steering wheel from about 54mph to 60mph and when the brakes are applied there feels like there is a significant wheel "hop" or elevated level of shimmy that goes away when the speed goes under 55. I rotated the tires in case there was a tire out of ballance but it did nothing to eliminate the shimmy. I can't tell if the steering dampening shock absorber is faulty or if the front struts are weak but I did check the tie rods and other connections in the front end and all appear to be in good condition. The vehicle has never been wrecked. What is causing this shimmy? Alignment? Please help - I've run out of options within my experience.