I recently bought my Touareg in Mexico and I think it is a great vehicle after owning many Jeeps the last 20 years! I thought the fuel tank was 100 litres. I've filled twice now from almost zero on the fuel gauge and can only fill 75 litres. Either the tank is smaller in Mexico (not likely I think) or the gauge is not reading properly. I don't want to run the tank to empty but is there some other way to confirm the tank capacity?