I've always called it a 12 gal tank when someone in the general "non-jeep" population asks. Even though it's 15 gal in volume, the filler neck extends into the tank so that only 80percent of it's capacity should be functionally usable. The top 20percent is for vapor. Although I can generally get 13.5 gal into it by parking on an angle, the extra fuel will often be regurgitated if it isn't quickly used up.
My tank is a steel aftermarket. It's 22 gallons. It was on the Jeep when I bought it. It came from a company in Idaho or Montana. Don't know which the tag was half torn off. I don't really like it. It sets below the springs and my diff. protector hits when I'm off the beaten path. Both are fixable with a BIG hammer.
80' CJ7, 360 Howell Injected, 3" single exhaust, NP435 4spd, Dana 300 AA clocking ring, Currie twin stick, Tera-Low 4 -1 kit, Dana 44 front, cut 10" wider to 63", 4.10 gears, ARB, Yukon axles and Super H/D u-joints, Currie Dana 44 rear, cut wider to 60 1/2", 4.10 gears, ARB 35 spline, Currie 35 spline axle shafts, 2 1/2" x 11" Ford drum brakes, CJ-SOA conversion, Tom Woods F & R drive shafts, Warn 9500i winch, 6 point cage, Homemade F&R bumpers and tire carrier, 1" body, Pro Comp supension Kit, 12.5x35x15 BFG's, 15x10 OMF beadlocks, Body armor, OBA.
I recently pumped 14.4 gallons in my CJ8 at the local gas station. At the time I was going by miles driven. Got my Auto Meter gas and temp gauge installed last week. Built a small panel out of aircraft aluminum for volts, oil pressure, gas, and temp gauges. I don't listen to the radio so the new gauges are positioned where the radio was. It's a neat little four gauge panel. Two over two.
Yeah, if you've gone aftermarket with your tank, you could have damn near anything, but I believe the OEM plastic was 20 (or 21??), but of course, now I can't find LEVE's thread where he spelled it out. Personally, I've never had anything but the 15 gallon, and I just replaced it with a poly aftmkt tank too...
I was curious where people stuffing all that tank when they go upwards of 20 gallons! scraping the diff is not so good, especially if you're a trail man... Looks like you need more lift