I have a new 07 Liberty and am getting conflicting information about towing capacity. I do not have the towing package (which is rated to tow up to 5000 lbs), but I had the dealer install a hitch. I have the 3.7 with automatic. The dealer told me that this set up would tow 4000-4500 lbs without the ****** cooler. The owner's manual seems to suggest a limit of 2000 lbs without the towing package. Who is correct?