camperjohn -

The airbags don't make a huge difference, but they firm up the rear of the van.

The airbags stay in the van all the time - but you can vary the pressure. The manufacturer recommends a minimum of 5 psi (just enough to keep the bag in place and ensure it doesn't get pinched by the spring) and a maximum of 35 psi.

I tend to put about 25 psi in them when towing. If I think of it, I drop them down to about 15 psi when not towing. The van handles better with the bags, even when not towing (but I've always felt the rear end of the Windstar was too soft).

I purchased my AirLift 1000 airbags here:

http://www.rjays.com/Air_Lift/airlift-1000-01.htm

Cost was $80 + shipping. I travel with a portable 12V air compressor so I can adjust the pressure, if needed.

Please let us know if you find the connector in your van. I still want to check a friend's 2001 Windstar, but haven't gotten to it yet.