Having read this thread, and being a new '98 Rodeo owner (with the 3.2L V6 and Auto tranny), I decided to check my mileage too. Over three recent fill-ups, I'm getting 14.5 - 15.2 MPG avg - mix of city/hwy driving. I think I've got taller gearing than stock, and my truck has 33s and is lifted. So I guess I should think this isn't too bad.

I've got no idea why your mileage would be so bad - maybe a full tune-up would help? or maybe your truck has had some very tall gears installed? One other idea - can you verify your tranny hits 4th gear (OD) on the highway?

Tom