All cars put out tons of moisture. If you look at some cars in traffic on a really cold day, you will see clouds of condensed steam. The cars put out the same amount every day, we just cannot see it.

If I remember correctly, a simple chemical reaction formula will show 22 gallons of water for each gallon of gas burned.

Perhaps someone who went further than freshman chemistry can correct me.
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3 8s & 2 7s 725,000 miles total