Brand new 2011 E-150 Van Wagon. In-town driving - fine. Interstate driving at speeds over 50 mph, experience swaying, steering difficulty, difficult to control. Causes over correcting to which leads to more deadly situations. Add a little wind (10+ mph) and it is terrifying! Passed a truck at about 65 mph, tried to pull back into lane and had no steering control - it was like the van was "floating" - finally was able to control van. I have been driving vans for 25 years-new Ford vans for at least 15 years, so I am not a novice and these are new vehicles. I would be a fool to pull my boat or anything else with this van.This is going to lead to serious/fatal accidents - rollovers, etc. Working with the dealership for a solution.