My vehicles don't use any fluids (except wiper fluid), but I carry a little oil, 50/50 coolant mix, wiper fluid, FP60 and paper funnels, and ATF/gear oil all the time anyway.
I also carry a tire gauge, a fire extinguisher, flares, refletive triangles, a headlamp, a blanket, two space blankets, duct tape, an emergency whistle, a first aid kit, a belt repair kit, a hose repair kit, drinking water and an Uno deck.
In winter I also carry chains, a snow brush, an ice scraper, a collapsible snow shovel and a can of de-icer.
Yes, I was a Boy Scout.