The statute of limitations is usually longer for state tax returns. The federal three year rule has some EXCEPTIONS: The assessment period is extended to six years instead of three years if you do not report income that you should report, and it is more than 25% of the gross income shown on your tax return.
Mike The Jeep Grand Cherokee in 2001 holds about 16 gallons. My 1996 Jeep Grand Laredo will hold 21.5 gallons, coasted into gas station once and it filled to this amount. My 92 Cherokee Laredo has a 20 gallon tank according to the owner's manual (and a few trips to the gas station). The Haynes Repair Manual for Jeep Cherokee - 1984 thru 2001 mentions however, that there were some with 13.5 Standard and 20 Optional. both above answers are correct.
Still nothing to scoff at, though. According to fueleconomy.gov, front-wheel-drive Cherokee models with the base four-cylinder mill will top out the lineup with 22 miles per gallon in the city and 31 mpg on the highway; opting for four-wheel drive with this engine drops the figures to 21 city and 28 highway.