You can do it without lifting the van. From below, there's a plastic butterfly wing nut attached to a rubber hose. Remove that nut, and the antifreeze will flow out. Re-tighten, and refill. (this is how it's done on the 95, so I assume all previas are similar).
On the side of the silver canister
11.1
changing front brake pads on 1991 Toyota truck
Pull the motor out of the car and change it.
go see a mechanic
A wrench
There is no cabin ari filter on a 1991 Totyota Previa
Change a air filter
a4ld
Try Google.com
Water/antifreeze
5.8 quarts