Different size tire change, Summer to Winter

Rims are sized to fit what's behind them; converting to smaller rims will likely interfere and they won't go on without hitting something. Besides that, your Ford rims have a different lug pattern and won't bolt on..... If you're financially strapped, buy simple 17" rims at a salvage yard that are designed for your minivan and spring for good winter tires; in the long run, they'll be the least costly per mile than cheap tires.

Yep buy cheap rims from a wrecking yard for your van, then buy Snowflake or Mountain design winter tires, in your area studded would be preferred as your only going to run them in the winter. Now without TPMS sensors you will have that light but if it’s just for winter you can get by ignoring the light.

Ed is right, 16 inch rims will not work with your vehicle. Purchase a set of used 17 inch wheels that fit your specific vehicle and winter tires to match. Safety first.