I have suddenly noticed a major dropoff in MPG, and the timing seems to correlate with my last xcursion. Background info: My X has 3k miles, is about 2 months old, and hasn't been in any shop since it was driven out of the dealer (am going in for an oil change on friday though). I have kept track of gas mileage since I purchased it, and I was pretty consistently getting 17 MPG. I then went on an Xcursion a couple weekends ago and am now getting 13 MPG :eek:. Can anyone think of a possible reason for this (mud, something jiggling loose, damage from hosing down engine, etc) :confused:? I also moved to a 31" tire at the same time but my speedometer seems to be right on and i don't think it would account for 4 MPG difference.

Thanks

I know when I put on the 31" Swampers and load up with camping gear and everything I only get 12-14 mpg! But a lot of that is spent in 4lo idling up and down trails and waiting around for my turn on the next obstacle. I have 30k on my truck and have had it 13 months and I average 16-18 mpg normally with the Grabbers on it.

I don't know why you had such a drastic drop off in economy though? Maybe some of the guys that have had their trucks two years can help you more? :confused:

Sorry I should clarify. I fully expect to get crappier than normal gas mileage when offroading. I have seen 13 MPG now for a couple tanks of gas since the xcursion doing normal city/highway driving.

That's about an 18% drop, certainly more than the 5% difference in tire size, and even adding in the extra pedal-to-the-metal time you probably engage in to make up for the decreased "oomph" from the taller gearing, it's still a stretch.

Check your air filter perhaps?

Brent

On our last Xcursion to Naches, my mileage offroad was a pathetic 9 MPG!! I average 19 on highway, 16 in city ... but this was the first time I ever got down below 10. I was in 4low almost entirely the 70 or 80 km's offroad.

Originally posted by OffroadX
That's about an 18% drop, certainly more than the 5% difference in tire size, and even adding in the extra pedal-to-the-metal time you probably engage in to make up for the decreased "oomph" from the taller gearing, it's still a stretch.

Check your air filter perhaps?

Brent

Ok I checked it this evening. The filter looks ok. There was a lot of dirt and pine needles and crap in the bottom of the housing for the air filter. I blew most of it out, but there is still some stuff in there. Should i take the time to clean it real good?

As for the mileage, I may be imagining things but it seems to be getting better as I near the end of my current tank. I used to be able to see it move as i drove only 10 miles but not so much now. I had been filling up at the QT b/c it was cheap but it dawned on me that my last tank (about 3/4) i got from Mobile instead. So maybe i just got several bad tanks of gas from QT? I'll keep my fingers crossed and tell you if anything interesting turns up.

Thanks.