Re: Changing antenna
I put a $10 5 inch short and stubby rubber antenna (mangowalk) on the spouses liberty for the same reason. If I try hard I can find just a little affect on AM and FM for those stations with marginal reception to begin with, but she listens to sat anyway which is not affected. You'll notice no difference on the stronger signals. The antenna looks good, better than the long thin OEM IMHO, and has been on there two years without issue. Make sure the replacement antenna has the right kind of threads for the chrysler base (I don't recall the chrysler thread) but this one and many others come with adapters.
Very easy screw off old, screw in new install.