Water Pump, Rein - 135i/335i/535i, X3/X4/X5/X6/Z4 35i (N54, N55)

The water pump used in the 2007-2015 N54 and N55 turbo 6-cylinder cars is electric and plays a vital role in managing temperatures for multiple systems throughout the car. However, because it's electric, when it fails it does so completely and without warning. We strongly recommend replacing the water pump before 80,000 miles.

BMW changed to an electric pump to reduce emissions and make the engine more efficient. Pumps driven from the engine accessories used up fuel which made for more emissions. Electric pumps only work when they are needed and only require the alternator to supply power. Because the engine computer regulates engine temperatures, the water pump only needs to work when it has to (including after the car has been turned off). In theory this should make the pump last longer. But it's the electronics inside that fail and will force a replacement, often without warning. Although if you are religious about oil changes and checking/clearing fault codes you may get a soft (hidden) code for low water pump output ahead of time.

The three (3) mounting bolts for the pump are required. In an effort to reduce weight BMW uses a very light weight bolt that can only be used once. See BMW part #11517602123 for replacement bolts.

This part is manufactured by Rein (CRP) Automotive - an original supplier to BMW for many various BMW parts. As an OEM Rein strives to meet all of BMW's original design, fitment, and performance requirements. OEM-type 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.