What type of power steering fluid does the 2001 ford f150 use?

Your 2001 Ford F-150 will use automatic transmission fluid in the power steering system -- the best type depends who You ask. Mercon is what's recommended in the manual, but some prefer Mercon V as an updated solution. Universal power steering fluid is also sometimes used, but it's recommended against by the manufacturer. So, at the end of the day, what's best to use There's no single definitive correct answer, but You should not mix different types of fluid. If You just picked up the F-150 preowned and don't know what's in the reservoir, it's best to vacuum or drain the fluid and replace with Your preferred fluid. Personally, I'd use Mercon V, but it's essentially up to You, with whatever You have on hand.