Transmissions are usually a weak point with Chrysler minivans.That's not to say your tranny will go for sure but they're worth keeping an eye on.
Here's a link that can shed some light.
http://www.allpar.com/
Not COOL!
I figure being able to drive in heavy snow and rain,hauling seven people,while gettin' 25mpg is pretty cool.Then you can haul sheets of plywood on the return trip.
Check the brake fluid,if it's anything but clear it nees to be changed.The brown color indicates water in the system and the water WILL corrode the lines and caliper bores eventually.DOT 3 is supposed to hold moisture in suspension like this so the water don't freeze and block the lines.
A trans fluid cooler might be a good idea if you do a lot of driving in heavy traffic.