I could be wrong here, but I believe that sensor 2 is to the rear of the catalytic converter. They are very very very easy to replace yourself (especially if it's the rear), just make sure you let the truck cool down for an hour or so before attempting. I'd suggest sticking with an O2 from the dealership, just to be safe. You wouldn't want to go to AutoZone or Napa and have them sell you a Bosch... <img src="/forums/images/graemlins/kewl.gif" alt="" />

'99 Tacoma Xtra cab V6 TRD
TRD Supercharged, URD 7th injector and 2.2" pulley, 32X11.5 BFG All-Terrains, OME 881 3-inch lift/Toytec AAL, 5100 Series Bilsteins all around, and ProComp 130 lights.
No I'm not some creepy naked guy...