Good job! I have to do this and other tasks on my /04 E60 (545i). Today, I am ordering from AGA: coolant pipe, secondary air port cleaning kit, and valve stem seal replacement tool kit. Also will get valve cover seals and stem seals. Total cost is about $1850. My E60 has 120k miles and all three problems showed up within the last 5k miles or so. Can't wait, ugh!

Goood job and nice writeup!

Btw, those "rain gutter support things" are called bulkhead (left) and partition (middle and right). I know this only because I had to replace all 3 and had to look for part #s.

Goood job and nice writeup!

Btw, those "rain gutter support things" are called bulkhead (left) and partition (middle and right). I know this only because I had to replace all 3 and had to look for part #s.

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Nice Job. Now throw the 2.0 bar coolant cap in the trash and replace it with 1.4 bar cap from a 1 or 3 series, buy it from the dealer, not the aftermarket, the inside of the cap will be yellow, and the package should say made in Austria, it is manufactured by Behr. Do not use aftermarket cap. The rear bellhousing coolant pan will be the next leak if you fail to do this. Summertime is hard on these cooling systems and the 29 PSI of pressure. I have been running the 1.4 bar cap for 6 months in Florida with no issues.

Correct me if I'm wrong, but if you haven't had any venting through your 1.4 bar cap, that means the pressure hasn't ever gone over that pressure and it really hasn't made a difference.

Pressure builds up in the cooling system after shutdown on hot days mostly, releases as the coolant expands. The cap also contains a vaccuum valve to where the coolant reseads when cooling down. You could say it has a 2 way valve. The cap is as important as the thermostat. I sense the 2 bar cap is more envirnmental than functional, though some will say it is for higher boiling point which is also true.... ethylene glycol is an envirnmental hazard when overflowed, this can be a risk with a lower pressure cap, I have not experienced it yet on my 4.8.

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Wow great write up. This showed me a lot of info on parts I need to remove to get to the altanator to remove it so I can get to the oil cooler connector seal on the block. I have a horrible oil leak right now from that connection. Thanks for all the good info.

You are correct. When you remove the power steering lines you will have to remove the idle roller followed by alternator.
Get ready for a really tight fit. You will have to pull alternator forward and undue all connections with it down in the bay. There really is no slack but about 5".

Good Luck.

Thank You, I will edit the writeup.