Pushrod, sorry to hear about your 4.8i wow's.

But this is exactly why I dumped my 2008 X5 4.8i and replaced it with a 2011 X5M with an extended warranty. I managed to spend over 8K in parts/maintenance in 6 months on my 4.8i. I did almost all the work myself and it seemed like every weekend I was working on that car. I will say so far the X5M has been significantly more reliable, and less expensive to maintain. In fact even though my 4.8i was paid for, I was averaging 1300/month in repairs. I have a spreadsheet that tracks costs, but damn, everything broke, sunroof, alternator, pcv, diff seals, suspension, e-brake, thermostat, heater control valve, MAF, etc. My X5M with an extended warranty costs my $435 in payments. It was money saving for me.

Oh my 2008 X5M 4.8i with 96K miles and 0 issues other than bad valve stem seals (which weren't noticeable with ATP-205). I traded mine in march 2017 for 9500. It was a fully loaded X5 4.8i with adaptive drive, multi contour heated and cooled seats, etc. I like the newer X5M but there is an M tax, and oh my goodness are brake pads and tires expensive.