Hi folks,

I only drive my somewhat-new-to-me 97 F-250 7.5l (gas) supercab when towing... So when I was getting 7-8.5mpg I thought that was normal. Then, I realized that half of my first trip with the truck, from Dayton to Indy (130 miles), was without anything behind me... I did the math, and was getting 8-8.5mpg WITHOUT towing anything. ouch.

On my way to Grattan (330 miles each way), I noticed the check engine light came on randomly. I cleared the codes at the track, then towed back where the light reappeared. I had them read at the autozone (no OBD-II on this guy..) and found the O2 sensor was reporting a complete lean condition while the computer thought that was impossible.

Well, I bought a new O2 sensor.. after 2 weeks of penetrating oil, a bigger wrench, a bigger hammer, and a mapp gas torching to red-hot I got the old O2 out. I put the new one in..

I drove the truck this week on my 180-mile-commute-to-work instead of the car - the difference with the new O2 sensor is amazing. The truck pulls better, sounds better at speed, and....instead of 8mpg - I'm around 14 or 15 (havent filled up, but used to go 240 miles on both tanks full - 33 gallons) mpg..

So - it was taking my truck 2 hours of towing to finally flick the check engine light on to trigger the O2 sensor bad... Might be worth replacing (at $58) if you're down on MPG lately...

hope that helps,

Mike