Oil capacity? 91' explorer

I would like to change the oil on a friends 91' explorer but I am not sure how much oil the engine takes. Its a 4.0L engine. I am unable to find the owners manuel to check the specs. Any reply would save me some time, and is greatly appriciated!

5qts., Put in four start engine, check dipstick and if low add the 5th quart.

Thanks- that should save me some time and worries!