Well, today, I started up the truck to move it into place to change my diff fluid. Not 3 minutes later, I get a check engine light. I pull the code, got a 23 and 44. O2 and EGR. No biggie I say to myself. I got an sensor lying around, I cleaned out the EGR, cleaned out the buildup from the TPI area with some carb cleaner, redid my K&N filter, then I tried... tried... to remove the 02 sensor. Funny how 3 years has a way of destroying the ability to remove it. Started using extra torque (my foot). It started tearing out the weld nut. Darn rust. I think Im just gonna sawzall the dang nut off, and just jb weld on a new nut, and then thread in the new 02. Wacha all think? BTW, my mechanic must have a funny sense of humor, why is my diff fluid... blue?