1. Mr. Fusion powers the Flux Capacitor. You still need gas to power the car.
2. I feel your pain, and you know I love the FlyingFamily, but you were amply warned in the search thread that the older Xterras get bad gas mileage. I think there is a certain degree of variance in the Xterras. People claim anywhere between about 15-20 mpg equal driving on stock vehicles. For what its worth, the engine in the older X is a slight bore and stroke on the old Pathfinder engines, and those trucks exhibited the same kind of variability in mileage. What kind of mileage did Wil get on the trip from Fort Collins?
3. Are your mileage numbers GPS confirmed? If not, it may not be as bad as you think. Then again, it may be a lot worse. :elkgrin: Even if the speedo is accurate, run a GPS for a tank and let it calculate the mileage. I have discovered that the speedo and odometer don't always match. On my sisters' Outback the speedometer and odometer are dead accurate. On my wife's Outback, the speedo is way off, but the odometer is accurate (didn't know that was possible). My point is that even if you matched the speedo against GPS, your mileage may still be off.
In my experience with the Pathfinder, synthetic fluids make a big difference in mileage. Confirm with the BN Guy, but you probably need to run GL-4 in the transmission, GL-5 would eat the bearings on a manual.