Again, BMW and plastic parts. I can't believe this X5 used to cost $55,000 brand new. What a stinkin rip-off for something that uses plastic engine components. Anyhow, the expansion tank is like a reservoir tank except the plastic will become heat fatigue and eventually will split and develop cracks causing coolant leakage which can lead to a severe overheat and eventually a $5,000 head gasket job.
My advice: Change out the plastic cooling parts every 50,000 miles or so.
Again, BMW and plastic parts. I can't believe this X5 used to cost $55,000 brand new. What a stinkin rip-off for something that uses plastic engine components. Anyhow, the expansion tank is like a reservoir tank except the plastic will become heat fatigue and eventually will split and develop cracks causing coolant leakage which can lead to a severe overheat and eventually a $5,000 head gasket job.
My advice: Change out the plastic cooling parts every 50,000 miles or so.
- M M., Oakland, CA, US