My 99 F150 extended cab squeaks alot. sounds like the back 2 doors are rattling, what could be the cause of the back doors rattling and how can i fix it?

 

did you put WD40 in the hinges? That could help a little.

 

common fo rthe door gasket ( rubber seal) to squeek. clean the rubber door trim and wipe something like armoral, or the same thing you shine your dash with. see it thats it.... then have someone set in the rear seat and touch things when you drive down a bumpy road to narrow it down.