Main Drive Belt, 6PK1990 - E82 128i, E9X 325i/328i/330i, E60, X3, X5
OEM replacement belt covers the power steering, alternator, and A/C
The main drive belt runs the power steering pump, alternator, and air conditioning compressor on the N51/N52 engine (the water pump is electric). It's very important not to neglect your drive belts as a failure will leave you stranded. The 2006-2013 6-cylinder engines (N51/N52/N54) also have a reputation for "eating belts" - the belt fails and is sucked into the oil pan. 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 catastrophic failure.
If you can, inspect and test the pulleys before ordering your belt - tensioner, deflection, A/C, and power steering. Or plan to order new pulleys and tensioner with your belt. These 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.
Also test the belt tensioner at the same time as the pulleys. A failing tensioner can let the belt slip off the pulleys. Due to the severity of failure, we recommend replacing the tensioner every 50-60,000 miles. But you might as well do it with every belt change.
E82 / E88 (08-13) > 128i
E90 / E91 / E92 / E93 (06-13) > 323i
E90 / E91 / E92 / E93 (06-13) > 325i
E90 / E91 / E92 / E93 (06-13) > 325xi
E90 / E91 / E92 / E93 (06-13) > 328i
E90 / E91 / E92 / E93 (06-13) > 328xi
E90 / E91 / E92 / E93 (06-13) > 330i
E90 / E91 / E92 / E93 (06-13) > 330xi
E60 / E61 (04-10) > 525i N52 (2006-2007)
E60 / E61 (04-10) > 525xi N52 (2006-2007)
E60 / E61 (04-10) > 528i
E60 / E61 (04-10) > 528xi
E60 / E61 (04-10) > 530i N52 (2006-2007)
E60 / E61 (04-10) > 530xi N52 (2006-2007)
E83 X3 (04-10) > X3 3.0si N52 (2007-2010)
E70 X5 (07-13) > X5 3.0si