Replaced alternater but it will not run without jumper cables hooked another battery
Get your battery tested, it may have enough voltage but not enough cranking amps to start truck, a dead cell may cause that problem.
Thanks that will be my next step
Battery sounds like it is shorted out. Do lights work, will horn blow, but not as loud without the cables attached?
Looking for a Used F-150 in your area?
CarGurus has 213,245 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