What's next folks? Have to buy engine oil, wax, differential lubricant, brake fluid, windshield washer fluid, carpet cleaners straight from auto manufacturers? I know there is a law, I just don't know what it says and how far it goes for consumers to use aftermarket product. Pretty soon, aftermarket exhaust systems will void warranties, etc. Looks like that's the new trend. Then oil changes and regular maintenance can ONLY be done by the dealer. That is just crap. The DIYer, like myself, is a dying breed. Except of course, after the warranty expires.