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Old 07-25-2011, 07:49 AM
sunny5280 sunny5280 is offline
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Location: Denver, CO
Join Date: Feb 2010
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Mein Auto: 2011 X5-M
Originally Posted by BMW1999M3FL View Post
Of course I don't buy into "lifetime" being lifetime of the vehicle. I agree with the people on here saying it is a marketing maneuver etc. I am a scientist (chemist), and I know about oil composition, metal particles, catalysis, heat effects, etc. Someone posted the ppm content of the metals and it is obvious that after 70K miles, the chemistry of the fluid is different. However, the difference is remarkably modest considering the length of time/mileage the fluid has been through. So the term "lifetime" certainly testify to the chemical resilience of the fluid, but not to its being consistently the same throughout the "lifetime" of the vehicle. I bet you that if someone tests the fluid after 12K they would find out that it has progressed toward deterioration already, and clearly a change may not be necessary at that stage.
Wouldn't this support the argument there is little risk to changing the fluid?

With that said I'm now just over 122K miles on my X5 and not a single problem with the transmission since changing the fluid 15 months and 14K miles ago.
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