The main drive belt runs the water pump, alternator, and power steering pump on the N62 V8 and N73 V12 engines. It's very important not to neglect your drive belts as a failure will leave you stranded. A belt is easy to inspect during normal maintenance such as an oil change or refilling your washer tank. If there are cracks running across the ribs, sections missing, the edges are frayed, or the threads are visible on the belt surface, the belt should be replaced immediately. Also pay attention to a belt that is running off the edge of a pulley as that is a sure sign of an impending failure.
If you can, inspect and test the various pulleys and belt tensioners before ordering your belt. Or plan to order new pulleys and tensioners for a complete overhaul. A failing tensioner can let the belt slip off the pulleys or allow too much slack, causing cooling or charging issues. The pulleys are made of plastic and shatter with age, causing potentially expansive/expensive damage to your engine, radiator, etc. They usually last longer than the belt but now is the best time to replace them. Since they are bolted on, not pressed, they are easy to replace.
This is an OEM serpentine belt manufactured by Continental - the original supplier to BMW for engine belts. As the OEM it meets all of BMW's original design, fitment, and performance requirements and is TUV approved. OEM parts are the best alternative to more expensive Original BMW parts because they are virtually identical without the inflated price tag. This part has a two year warranty.745i fitment note:
only for 2004-2005 model years (not for cars produced before 10/2003)
E60 / E61 (04-10) > 545i
E60 / E61 (04-10) > 550i
E63 / E64 (04-10) > 645Ci
E63 / E64 (04-10) > 650i
E65 / E66 (02-08) > 745Li
E65 / E66 (02-08) > 745i
E65 / E66 (02-08) > 750Li
E65 / E66 (02-08) > 750i
E65 / E66 (02-08) > 760Li
E53 X5 (00-06) > X5 4.4i N62 (04-06)
E53 X5 (00-06) > X5 4.8is N62