Two problems related to engine burning oil have been reported for the 2004 BMW 745. The most recently reported issues are listed below.
Engine valve guide seals made of improper material that fails causing oil leakage into exhaust, fouling of catalytic converter, failure to pass inspection and pollution. The valve guide seals are not compatible with high engine temperatures which causes the seals to fail at 80,000 to 120,000 miles. My seals failed at approximately 95,000 miles causing oil consumption in excess of 1 quart per thousand miles. Replacement of the valve seals requires extensive engine read down and costs approximately $9,000 to repair.
The contact owns a 2004 BMW 745li. The contact stated that there had been an extensive oil leak from the vehicle. The vehicle was taken to an authorized dealer several times but the failure was not able to be duplicated or diagnosed. The contact also described a burning metal and oil odor in addition to a while cloud of smoke. The alternator and battery were repaired twice by an independent mechanic however, the failure persisted. The vehicle was then taken to a different repair facility where the contact was advised that the alternator, alternator seal gasket, valve and seals needed to be replaced. The manufacturer was notified of the failure multiple times. The approximate failure mileage was 130,000. . . Updated 05/20/14.