[WhiteBeard]

Pre-LCI 2007 e90 with 37K miles. Coolant has same color and no sediments, looks clean, but it was changed 4 years ago. It's long due for change, but given the age of the car and the fact that it still has original water-pump, chances are that water-pump may fail any time now.

Worth changing coolant even if water-pump fails in a week or it's reasonable to wait until it fails (a good chance it may happen withing a year, after all car is almost 10 years old) and then change everything?

[Three_thirty_I]

My E90 is older and has a bit more mileage on it. Still the original water pump, but have changed the coolant a few times already, and more recently replaced the thermostat because I thought there was a problem with it. What makes you think the water pump is "going to fail in a week"? The fresh coolant will at least help keep the coolant hoses in good shape, and they are more of a PITA to replace than the water pump and thermostat.

[mweisdorfer]

Originally Posted by WhiteBeard

Pre-LCI 2007 e90 with 37K miles. Coolant has same color and no sediments, looks clean, but it was changed 4 years ago. It's long due for change, but given the age of the car and the fact that it still has original water-pump, chances are that water-pump may fail any time now.

Worth changing coolant even if water-pump fails in a week or it's reasonable to wait until it fails (a good chance it may happen withing a year, after all car is almost 10 years old) and then change everything?

As long as you are not tracking the car, the OEM coolant should be good for 100k.

I would not worry about it until you get to 75k.

The 2-3 gallons coolant should on your check list of items needed if you intend on proactively changing the water pump, thermostat & U shaped pipe once you reach 75k.

[Efthreeoh]

The coolant change is called for at 100,000 mile intervals. It probably doesn't need to be changed. If you do change it, you can always drain it into a clean container and re-use it. Back in the day, I changed my t-stat, and 4 months and 15,000 miles later the water pump died. I just reused the coolant when I replaced the pump. I changed that coolant out 84,000 miles later when I replaced all the coolant hoses.