2000 Windstar LX, how to know if equiped with load levelling

It's time to replace the rear shocks and while pricing at y2kFord.com (http://www.trademotion.com/partlocator/index.cfm?action=getLocator&siteid=214072&chapter=DP2027&appSectionid=24&groupid=20135&subgroupid=61669&componentid=0&make=10&model=Windstar&year=2000&graphicID=T027090&callout=5&catalogid=1) I get 2 options for my windstar, with and without load levelling so how do I know which I need?

Also RockAuto, AutoZone and Advance Auto Parts don't ask about load leveling while pricing...!

Since I'm at it what shocks would give me the best value for the money I can get some Gabriels, Monroe or else I would like to keep it as close to the original Ford feel as possible, but at $45 a piece from y2kFord it seems a little high for my budget.
Any help is greatly appreciated

Load leveling refer to air bag spring at the back which is control by a computer who adjust the rear level according to the load weight.

oh, I see!

I don't have that kind of rear suspension... good deal! since the shocks for load levelling cost almost thre times as much as regular rear suspension.

Thanks for clarifying catvents