Preventative maintenance is ALWAYS cheaper than catastrophic maintenance.
Components wear down and fail. One could literally drive the car off the lot and never
raise the hood. Years could pass. Eventually the oil would fail, the air cleaner would clog, the MAF would
gum up,the oil filter would clog.
Yes, those are all items that need attention.
I don't wait for those items to fail. Keep on top of your vehicle and stay in the fast lane.

I come from the Aviation background, and failure in flight , is not an option.

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2003 4.6is X5
2003 525it
2003 E53 X5 Standard shift