Originally Posted by kcsf

So I bought a 2012 X5d with 60k miles last month after driving E53's for the past 18 years. On the drive home I closely watched the MPG's expecting mid-high 20's. I got 21mpg and I knew something was wrong. After searching through here, I theorized the thermostat was bad as the engine coolant never rose above 78*c. Last week the engine light came on, and error P0675 (bad #5 glow plug) confirming my suspicions.

Replaced:
Thermostat
waterpump
glow plug module
coolant flush
oil and filter change

This all took only about 4 hours as I've replaced most of those items on prior e53's. It would've taken ~3 hours had I not snapped off the coolant level sensor beneath the reservoir. $600 in parts, $0 labor. BMW gave me a quote of ~$3k, and my local indy ~$2500.

I also poorly replaced one coolant hose causing the hose to separate from its intended connection, spewing coolant, and stranding me on the road. A free AAA tow to the nearest store and off I go. Stupidity penalty accepted.

All and all, I'm loving the new truck and very thankful for this community!