If its a 1987 F150 it may have the either a C6 (3 speed D 2 1) or AOD (4 speed (D) 2 1 with the D circled or bold background), electronic overdrives didnt come out till about the 89 model.
It is what it is. A 25 year old truck that may need some maintenance and small fixes. First thing to do would to be replace all the bushings in the front end. Go through the brake lines looking for corrosion or rust and replace them. Make sure your tie rod ends, ball joints and U joints are in good shape or replace them. Other than that, you will have to school yourself on how to maintain vehicles to keep it around for a long time.