The warranty should start from the day you bought the car. Demos are legally treated as new cars (at least as far as the IRS is concerned for accounting purposes). The 4,000 miles will count the same as if you had driven them, but the warranty timing should not be based on when the dealer got the car. Otherwise, you'd always get a warranty slightly shorter than the full advertised warranty (e.g. if you bought a car a week after a dealer got it, you'd get, say, a 2 year 51 week warranty, which doesn't happen).
Originally Posted by frankydude
Personal Best Charge: 57.2 miles
Best Day: 71.3 miles, no gas (49.9 on full charge, 21.4 on ~4 hours @120V)
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