I don't think they have a "reserve" per se, but I know my light will come on at nearly 225ish miles on the tank and I only will fill up after 260, unless I've been traveling or wheeling. It's never left me out of fuel. If you want to find out what fuel tank you have for sure, look at the imprinting on the tank. Mine says TJ18, which means I have a 18 gallon. Don't know for sure if you'll have it, but its worth a look.