it would appear I spent too much.
ANYWAY.....What does everyone think about a new oxygen sensor after 257,000 miles? I certainly would "think" I should see an improvement. But I suppose its possible that the original one is still functioning exactly how its supposed to and I wont see any difference whatsoever. We'll see.

 

You wont see much of a difference. Most of it will be in your head.

These trucks use speed density electronics. The computer is programmed one way. And the o2 sensor only fine tunes the stock fuel mixture.