Check the coolant, make sure it isn't going there. Otherwise it is either leaking or going out the tailpipe.
Also check de PCV and the hose. Any reason you should think high crankcase pressure like say... a popping oil stick?
How many miles on the engine?
How much oil are you losing? You can probably burn more than a quart in a thousand miles and not see any smoke at all.
Looking for a Used F-150 in your area?
CarGurus has 213,211 nationwide F-150 listings starting at $1,295.
Search Ford F-150 Questions
Ford F-150 Experts
Related Models For Sale
Used Cars For Sale