Thank you sgrice! Mine has 170k miles and discovered the thermostat was stuck open, plus had a code for the EGR Cooler Performance. I followed your instructions, without which I could not have done these procedures. I discovered that the door of the EGR cooler was stuck, and the inside all charred up. So I wound up replacing that as well. It passed NYS inspection and running fine ever since.

Here is what I did differently from you:
1) I left in place duct #3 before the MAF sensor, no need for Tite Reach tool.
2) I removed the plastic cover below the fan shroud, and the steel cross member underneath it. Originally I was trying to find the coolant drain cock, but ended up cleaning a lot of leaves and dirt out, and eased shroud installation.
3) I drained and collected about 2 gallons of coolant by disconnecting the long thin (about 35 mm) hose below the radiator shroud bottom cover. Minimal mess, and virtually no additional coolant leaking when later disconnecting any other hoses. Refilled the cooling system at the end with a vacuum filler.

Thank you again for the detailed work procedure that allowed me to brave this job!

2010 xDrive35d