New x3 owner

[srhorn]

Considering the condition of the transfer case we saw no need to analyse the oil...the shards did seem to be the result of bearing failure. The oil was VERY dark compared to new. Nevertheless, the TF0870 lubricant is not considered a permanent lubricant...and to replace it every 30-40K miles seems a reasonable measure. There is a documented procedure for replacing it and resetting the electronics. I plan to replace it in my 2008 at its next service. Electronic monitoring is fine, but as a Hardware Product Manager at a really big computer company...I can tell you they can't cover everything!

[JCL]

I wouldn't have analyzed the oil either, it won't tell you much from a single sample. If it smelled burnt, that would be worth noting. Colour wouldn't matter at all. Metal particles won't show up in a standard fluid analysis, but would show up in a large particle analysis. Without trendlines, though, not much value.

I would have opened the case to see what caused the failure, out of interest. Look at all the ZF transmission failures that relate to things like snap rings. Changing the oil early, as good as it feels, won't make snap rings last longer.

But as long as you do the reset when you change it, I agree it won't hurt to change it early.