Recently my engine light came on, went had it diagnosed. store said it was my oxygen control senors on both sides of my manifold. question is this: where on the manifold is it located and is it hard to replace yourself, instead of paying a garage an arm and a leg for that service.
besides all that, how many sensors of this nature are on the truck and should i worry in replacing them also?

 

They should have told you whether they were upper or lowers (or it could be 2 up and 1 lower). Uppers will be located before any of the cats in each manifold. the lowers will be after each cat before the Y pipe. If you can get to them they are not bad if you have the socket to remove (or borrow one). Some can be a real bear to removeif the engine is cold, however some can be painfull if the engine is hot. Just look for the shiney round pieces stick out of your exhaust.

 

If you retrieved trouble codes for a 'lean'condition on both right and left bank 02's it usually isn't the sensor themselves.. Many good 02's have been replaced for those codes!! Couple things can cause R&L bank lean DTC's, one being a debris contaminated mass air flow sensor (MAF),, in that theinternal 'hot wire' that detects and cools as air movement passes through the sensor collects dust/debris and insulates the sensor wire which can throw the needed values off and the system goes lean.. The other is the intake oring's that seal the intake manifold will leak/bleed unmetered air into the intake causing a lean condition.. Usually verifyable by spraying carb cleaner around the manifold base for an RPM change., or if severe enough can cause an unstable idle cold, that at times, improves as the engine temp rises. Also any other points, vacuum lines, PCV ect. where unmetered air entering the intake can/will set the lean DTC's

 

Hayapower is right. I replaced all four O2 sensors and still had the same problem (if the code set was for a Lean Left or Right Bank). I finally fixed it by replacing the 3 O-Ring type upper manifold gaskets. The gaskets took 45 min to install and cost $ 10.00 from Ford. When you had it scanned, did they tell you what code was set?

Ralph...