so i've noticed lately that the rear end of my coupe feels like its 'loose' when i'm on the freeway. it feels like its floating or wagging side-to-side when i get up past 50 mph. it doesn't happen often, but i usually feel the sensation at least once when I'm on the freeway.

is this something that can be corrected by adding sway bars or do I need to have the rear wheels re-balanced?

 

When wheels/tires arent balanced, you will receive a shaking in your steering wheel at higher speeds. This sounds more like an alignment issue. Have you dropped your car? Have you hit a hard pothole?

 

haven't dropped it, but will be doing so in a week or two. guess i'll have it realigned when i get the rear cambers on. thx for the advice!

 

Your toe is most likely off.