do all 2008 Titans come with a tow mode button, or just the ones OEM equipped from the factory?
Most (if not all) frame mounted trailer hitches are aftermarket. Ford, Chevy, GM, Cadillac, Dodge, Mitsubishi, Toyota, Honda, Nissan and Lexus I know are all aftermarket. Lamborghini (the only SUV), Porsche, Land Rover and UniMog make their own.
TO ANSWER YOUR QUESTION - Yes they all come with "tow mode" because they assume people will one day want to pull a trailer with it and turning the switch "On or Off" (however you describe it), does not allow the trucks transmission to shift into overdrive (keeping it from ruining the trans).
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