haven't had a chance to get underneath lately to notice but wasn't sure if there 2 or 4 of 'em - looks like the same part number for upstream and downstream units though...

 

Four, same as on every other F150 since 1996.

Steve

 

The ones you need to worry about most are the front 2. All the back ones do is verify the fronts are working if they fail youll get a cel, They last forever back there though. the fronts are more critical because they send data to the computer that affects how your engine runs and they get old and less effective and should be replaced.

 

thanks for the tip - @ $50 a hit, that's a lotta green I can put into the truck somewhere else!