Coolant Flush

I'll keep this one simple. How often should I do a coolant flush?

Originally Posted by RipSnort535i

I'll keep this one simple. How often should I do a coolant flush?

IMHO anywhere between 35-50K's would not harm your car. Question, I ask is how to do you flush it ? I only drain my E60 M54 525i radiator, as I don't know where the engine coolant drain plug is. So are you referring to flushing or draining? And if draining, how do you drain the engine block. Can that be done by disconnecting the lower radiator hose?

I view coolant as more of a time sensitive, rather than mileage sensitive issue. While BMW says it now is a lifetime fill, I change it every 4 years.

5 years

Originally Posted by Mac Hadley

I view coolant as more of a time sensitive, rather than mileage sensitive issue. While BMW says it now is a lifetime fill, I change it every 2 years.

Very helpful. Thanks to all for the replies.
I am approaching 60k and need to look at some preventative maintenance.

Originally Posted by kskane

IMHO anywhere between 35-50K's would not harm your car. Question, I ask is how to do you flush it ? I only drain my E60 M54 525i radiator, as I don't know where the engine coolant drain plug is. So are you referring to flushing or draining? And if draining, how do you drain the engine block. Can that be done by disconnecting the lower radiator hose?

Could find the engine block drain plug so only changed the radiator fluid and whatever I could squeeze out of the hoses leading to the pump. Drained close to 7 liters although capacity is ~11 liters.

I will change it again in a few years.