This is kind of a gloat... but some of you might enjoy it...
I have owned my jeep now for a couple months and started to plan some of the modifications I want to make. I have spent a lot of time browsing web pages and one particular modification that caught my eye was to increase the capacity of the gasoline tank from 15 gallons to 20 gallons.
This might be a rehash of previous discussions on this topic, but in case there is someone other than me left out there that had not made this mod, it might ease your pain some. Not much, but some.
My jeep seems to get about 15-18 mpg. A tank lasts about 225-250 miles, so I end up stopping to fill up around 200 miles. For daily driving and short trips, this is not that significant. However, I have some longer drives planned later this year (Moab?) and coming from Texas, I might want a little more range from the tank. I know, it will take about 3 hours to go 200 miles, and that is a reasonable time to take a break, but humor me... I am male and if I can get more, I want more. Especially if it is "free."
There are a couple really good websites out there describing how to do this that have some detailed pictures. After looking at these and reading them several times, I convinced myself that even I could do this.
This started for me during a browsing session for general upgrades where I saw a replacement 20-gallon tank for like $500. I made a mental note about this and later decided to see if there were cheaper ones for sale. This is where I stumbled upon one of the modification pages describing how to do this conversion.
For those of you who are not familiar with the situation, Jeep offered a 20-gallon option instead of the 15-gallon standard tank. In reality, it is the same tank. The difference is that the 15-gallon tank has a vent tube inserted that traps a 5-gallon bubble of air at the top of the tank. If you shorten the vent tube, you reduce the size of this bubble and the tank will hold more gasoline... so this is the premise behind the modification.
I was especially encouraged by comments indicating that the mod could be made in 30 minutes or so... that one of the posters fiddled with dropping the gas tank so it took about 90 minutes. My warning here is that your results may vary; translated this means your results WILL be worse.
On a nice sunny Saturday morning, I recruited my neighbor's son to assist. We laid out tools and set about making this happen. I quickly got through the part where you remove the cover from the rear tire well to the fill tube. When it came time to disconnect the fill and vent tubes is where things went sideways.
We looked at dropping the tank, but had issues due to the exhaust line blocking the passenger side of the tank. I think that during the manufacture of the jeep, they put the gas tank on the frame before they lowered the body in place. Hence, the hose clamps are on the top at an angle where you cannot easily get a wrench, pliers or socket in there to loosen the clamp... or when you do, there is no room to move it.
I take great pride in my work and abilities. So I found this to be quite frustrating. I also try to set a good example for my neighbor's son by limiting my use of foul language around him. After about 6 hours where both of us were taking turns trying to loosen these clamps, he was about as adept in the use of some of the more colorful reserved language phrases in the English language as I am.
I convinced him that using a torch to burn the hose off the tank was not an option... especially since there was a small quantity of gasoline still in the tank. (ok, it was more like him convincing me...) Finally, in total frustration, I took a pair of chanel-lock pliers and grabbed the hose next to the tank, and twisted. The hose slipped around and we were able to remove the clamp.
We were on our way. The vent tube came out and we cut it down to the recommended length and reinserted it. Everything went back together pretty quick. The hose clamps are now positioned in a more humane location. All said and done, it took about 7 hours to complete the mod.
Anyway, my neighbor's son rode with me to the gas station and I let him pump in the gas. I don't know who was smiling bigger as the pump went passed 15 gallons on up to almost 19 gallons. On the way home, I took the opportunity to explain that there were right and wrong times to use colorful language... I didn't want to be seen as a bad influence just in case I needed his help again.