Quote:
Originally Posted by AV8R4AA
Hey Guys,
I have 2 of these money pits. 2003 and 2004.
4.6 Big Red, and 4.4 Silver Bullet.
I know the N62 engine better because I have had it longer.
My new ride is the 4.6 M62.
My question is why does this engine wear out timing chain guides so fast?
Granted, it's now 13 years after it was built. But I have only 61K miles.
All the people that run that engine talk about chain guides and what a pain.
I can understand dry timing belts needing replacement at 100K miles.
Seems logical.
But an oil lubricated timing chain failing under 100K miles?
I would expect the timing chain and associated parts to last the life of
the engine.
I have owned many inline 6 cylinder BMW engines and the timing chain has never
been on the radar.
This M62 seems like it should last longer.
My question is why does these guides fail or begin to fail very early in life?
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Here is my theory on the wear. BMWs recommendations for oil changes for intervals is way too long. If the oil had been changed at more moderate frequencies say every 5000K from day one on synthetic then I am sure the guides would last a lot longer and better service. Keep in mind there are many people who get to 200K before the guides go. The material of the guides get brittle and once they go the timing chain makes it grooves and stretches some more keep going and jumps timing.