Power steering Ford ZX2

What would you guys do for a 2002 ZX2 (Escort) with only 40K and has BLACK PS fluid? There are no symptoms and there is no fluid change schedule. Should I just change it and pray? When I first looked for a cooler, I thought someone had stolen it. There is a loop of tube going in front of the radiator. I did find out that this is stock. There is plenty of room there, so maybe I should install a fin and tube cooler.

I would change the fluid and keep an eye on it.