2001 chrysler sebring convertible, steering wheel hard to turn in cold weather

I have a 2001 Chrysler Sebring convertible, 2.7 V6. I have a hard time turning my steering wheel when it's cold in the morning but even when it's warm, it's worse in the cold. I was told I need a new rack and pinion steering gear. Can I flush the power steering fluid, if so how? Also I was told to use the Lucas Power Steering treatment additive sold at Napa. Any thoughts or suggestions. Thanks