my VX was straight stock as it was off the showroom floor. At that time it only had 30 miles on the odometer. I filled it up with 89 octane gas which is California's lowest Octane due to the detergent they put in it to help save the ozone by providing better emissions. Due to this detergent being added the octane couldn't be lower, plus being at sea level anyway means you can not use too low of an octane.

From purchase date till 12,000 miles on the odometer, my VX was getting 400 to 410 miles per tank. Then it started to get 300 miles per tank. Replaced fuel filters, had injecters flushed and cleaned out, cleaned EGR, replaced Pcv, replaced spark plugs, everything lubed, greased, and any fluid that could be, changed out. to no avail. It still received 300 miles per tank till it hit 18,000 miles on the odometer and then it started to get 200 miles per tank. mind you that, my VX was still bone stock.

THen I did the fluid change thing again, filter changes again, egr cleaned, injectors cleaned, etc.... but, I installed a fuel miser, tornadoe, and a Calmini air filter. This boosted my mileage up to 230 to 260 Miles Per Tank. and this is where it stayed and is still the same.

So, when I did change the axle gears out from 430's to 456's and installed the interceptor, and went with 32x11.5x17 inch Super Swampers, installed rock slider bars, diamond plate skidplate, Chrome molly Tie rods, Chromemolly sway bar disconnects, and the stinky fab heavy duty rear drag bars, extra yellow top battery, rear storage box loaded with crap, and not to mention the 6 or 7 boxes of Dynamatt xtreme, and I started carring around all my tools(200 pounds), 12 inch speakers and 400 watt amp plus all the heavy wiring, full size spare on top, Yakima extended load warrior, Tow hitch, winch bumber, Warn XD9000 winch, and about 4 extra sets of rock lights under neath the VX as well as the purple neons, extra auxillary fan, etc. after all that I still was getting around 260 miles to the tank. Changing the gears out when I went with the larger tires brough me back closer to stock readings, but not exact.

The only thing that I have changed since then would be I removed the rear seats and went with 305 70 17 Goodyear wrangler MTR's. Now the reading says that I am only geting 200 miles per tank...but I need to find some 477 axle gears to make the reading more accurate .

for a small slant 6 cylinder engine this should not be the case.especially when it was only just shy of weighing 4000 punds stock...mine tipping the scales at around 5,000 pounds...considering that I was at the tire shop and they had a lexus off the ground with the hydraulic lift and the door just happen to be open so I read the weight of it. It weighed more than the VX stock as well as mine with all the heavy crap added to it. It was over 5,000 pounds in weight and those POS's get better gas mileage than our VX's stock.

Bottom line the VX sucks...in mileage and is the crappiest investment in a fuel economy vehicle, but it functions offroad and that is mostly why I bought it. I'm just saying that I might as well have a big 8 cylinder engine in it if it wants to get the mileage of one.