Let's talk about M54 coolant expansion tanks

[cn90]

- Search for the "partial cooling overhaul DIY" I wrote a while back when my 2006 X5 M54 was at 115K: Wahler tstat, reservoir, tstat, cap, belts, pulleys, fan clutch etc.

- If you have more than > 150K, then do a entire cooling overhaul.

- The reservoir, use BMW only. Interestingly, I bought this from a BMW dealer, who is trying the get rid of old stock for cheap. Normally, the reservoir is $100 or so, this (Century Auto BMW dealer) is selling it for $55:

https://www.ebay.com/itm/Genuine-BMW...1/122630659270

[Overboost]

Originally Posted by cn90

- Search for the "partial cooling overhaul DIY" I wrote a while back when my 2006 X5 M54 was at 115K: Wahler tstat, reservoir, tstat, cap, belts, pulleys, fan clutch etc.

- If you have more than > 150K, then do a entire cooling overhaul.

- The reservoir, use BMW only. Interestingly, I bought this from a BMW dealer, who is trying the get rid of old stock for cheap. Normally, the reservoir is $100 or so, this (Century Auto BMW dealer) is selling it for $55:

https://www.ebay.com/itm/Genuine-BMW...1/122630659270

I keep my X5 pretty nice and I just did the belts, tensioners, idler pulley and water pump. I had a soft fail thermostat last year so that was done then. The hoses look really good so I think I will leave those for now. I may end up buying a new level sensor since I have the tank out. I know the transmission thermostats always tend to come apart when you pull the tank so I have that on my list.

Any other suggestions I am all ears.