Took 3 hours to do it and at 2.5 hours I was seriously concerned I would have to take it to my local mechanic. 2 weeks ago I started hitting it (& the other 3) with PB Blaster after every drive. Started out using the correct O2 sensor socket and as I expected after looking at it, it was a waste of money (for this one at least). The cut for the wires allowed it to flex open just enough to slip around the sensors nut. Next I tried a wrench with a breaker bar. That popped it loose. That... Changed B2S2 O2 sensor. What a PITA