On my 2nd Transporter. Had the first one for nearly 8 years, this one is nearly 4 years old, "touch wood" not a single major problem in all that time. Never let me down, comfortable, spacious and will knock along when you need it to. Couldn't tell you what it does to the gallon, when it gets down to 1/4 full I just fill it up. 1st one returned me about 40% of what I paid for it after 8 years and 125,000 miles.