Supercharger Oil 4 FL OZ - BMW MINI Cooper S
The Eaton M45 supercharger fitted to the Cooper S is extremely unusual in that it has two independent oil chambers. One for the front nose bearings/gears driving the two rotors and the other for the Power Take Off (PTO) gears which in turn drive the water pump assembly. BMW MINI does not have service intervals for the M45 supercharger fitted to the R53/R52 Cooper S models. They deem the fluid a “lifetime” product. Great, but whose lifetime!?
The MINI superchargers are particularly susceptible to complete failures which typically are caused by the loss of supercharger oil in at least one chamber. Consequently, gears and bearings run dry resulting in metallic mayhem! A new supercharger unit will be required which will not be cheap!
If you are undertaking any work on your MINI where you have very good access to the supercharger unit we strongly encourage you to check fluid levels in both chambers and top up or replace accordingly. This supercharger oil is the proper approved stuff for the Eaton M45 BMW MINI Cooper S supercharger. Please note; to completely change the oil in the MINI Cooper S's supercharger you will require 2 bottles of this oil. A complete oil change cannot be carried out with 1 bottle. It's simply not enough.
Access to the rear oil chamber on the supercharger will require the complete removal of the water pump assembly to gain access to the drain plug for the PTO gears. With the supercharger still attached to the engine syringes will be required to suction out old fluid and pump in new fluid. These can be purchased on our online store.
Fluid brand/label may vary depending on current stocks and supply.
BMW MINI M45 Supercharger Oil Fill Levels:
- Front (Pulley Side): 145ml (4.9oz)
- Rear (Water Pump Side): 40ml (1.4oz)
Note: Sold individually in a 4oz (118m) bottle.