The dreaded crankshaft bearing issues with the BMW M3 – S65 engines. Let’s get the facts straight, the actual failure rate is extremely low considering the volume of cars built over the five years, approximately twenty six thousand (2008 to 2013 ) for the general public.
This particular engine has been built as a high revving normally aspirated high output performance engine pre-dominantly designed to compete with Porsche in the various road races over the years.
The first examples were squeezed into the E46 chassis. E46 chassis where they became legendary in Europe and North America. Worth to note, the same engine has been the sole M BMW Motorsport of choice in all the factory supported M race cars the M3 and the MZ 4 from 2005 until 2015 which speaks volumes about this particular engines durably. Its safe to say the engine is well built to perform. It preforms very well under racing conditions, and performs just as well under daily driving over the life of the engine perhaps.
However, there are a few things to remember, if you own one of this cars for instance the bearing load on the connecting rod will increase 25 fold from six thousand rpm to eight thousand five hundred rpm.
Because of the high revving nature of the engine we recommend to switch from the factory recommend TSW Castrol motor oil to the more robust build Liqui Moly 10-60 motor oil. Furthermore we also recommend to shortening the oil change intervals to maximum ten thousand kilometres at most.
Also we ad (despite that BMW not endorsing any additives at least not on paper) a Liqui Moly MOS/2 (molybdenum disulfide, graphite) additive which gets embedded in the bearings at each or at least every second oil change.
If you have oversized calipers and use your S65 equipped M3 for competition purposes you should convert your lubrication to a dry sump system, regardless of cost. The factory set up not designed with extreme G forces in mind period.
We have serviced many of this cars with this maintenance method, and never had a bearing failure even at spiritedly driven M3 cars at near two hundred thousand kilometres. Draw your own conclusions.
We wish you all the best and happy motoring from Techmax.
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