It's time to replace my 25 year old tank. I popped a hole in it over the weekend. I know 20 gallon was an only an option during the 87 model year. I also know the only difference between the 13 and 20 gallon tanks is the vent tube, but I'm not sure which tank I have. Build sheet doesn't say, believe it or not, and there aren't any stampings on the tank itself. Looking at the vent tube, which tank size is this? Thanks!

 

How much gas does it take to fill it up? If it is over 13 gallons than it is a 20 gallon tank. If it is less than 13 gallons than it is a 13 gallon tank. :-0

 

I would guess the 20 gallon as the vent looks to be far above the half way point. The 13 gallon should have the vent tube turning down and just over half way up from the bottom.

When I replaced the one in my 85 I just bought the 20 gallon because it was cheaper than the 13 gallon. Fuel sender is at empty when I have about 3-4 gallons left, but I just consider that my Reserve tank

 

Funny thing, I don't know. The only time I ever fill-'er-up is when I'm on the way for a weekend of wheeling. When I stop to get gas I always just fill up the jeep too! I don't drive her enough between "wheeling weekends" to need gas...

I was thinking the same thing but wanted some confirmation. I've seen the threads on the vent tube mod and the pictures always look like mine. I haven't seen a vent tube on a 13 gallon tank. Thanks for the reply!

 

Most likely a 20 gallon, I've only ever seen one XJ with the 13 gallon tank. Both my 87 and 90 have factory 20 gallon tanks.

 

It's most likely a 20 so that's what I'm getting! Thanks!!