After reading a few Jeep forums I found out that the difference between a 15 gallon tank and a 20 gallon tank is a little bit inside the tank. Externally, this equates to 15 gallons and 20 gallons of the same size. I can confirm this to be true as this skid plate fits my 15 gallon tank perfectly. It is exactly the same size, shape and design as the OEM skid plate that I replaced on my 95 YJ. Hope this helps some other old Jeepers!