Coolant replacement - how to decide?
 

So I had my car checked out just before its warranty ran out for any issues, and they listed that the coolant could use flushing. I presume they tested its strength somehow. Car is exactly 4 years old, and has 40,000 miles / 66,000 km's on it.

What do people here do? Can't find any info on it in the manual or by searching here, oddly.

On my car I change the coolant every two years . So in my opinion u should be on the second coolant flush. I also change the hydraulic fluid, brake fluid and the rear gear oil every two years also. The trany I change every 30,000 miles, some people say it's too often but my tranny shifts and performs like new. So frequent fluid changes is the best thing u can do for your car .

Thanks. What is the official guideline on coolant though? It's not every two years like brake fluid flushes I take it, as otherwise, I'm sure they have done it once at least by now. Is it one of those "lifetime" fluids in their opinion?

Not exactly sure what thier guide lines are for coolant ,,but i dont follow thier oil and fluid change recomendations... Dont believe thier life time fluid crap, especially the trany fluid life time B.S.

It's lifetime as long as your on free maint .. then changes to every other year (go figure:-)

:) lol!

Yup!

BMW's old recommendation was to change the coolant every 5 years.
Personally I don't see anything wrong with that.

I've changed mine every couple of years or so, by force or circumstance with this car (water pump, valley pan, expansion tank, and general phukkery). Im at 204,571 miles on her (and climbing at an average rate of 150 miles/day), so I must have done something right with this thing of mine LOL.

Your coolant drain frequency depends upon your objective. Depending upon conditions the life of the antifreeze will vary.

If you want to be sure it is doing the job drain it every two years.

If you want to squeeze as much life as you can out of it you can send antifreeze to testing labs just like oil, to insure that the critical additives that lubricate and fight corrosion are still doing their jobs. But the time, trouble and cost of doing this is more than the cost of two gallons of BMW antifreeze if you buy it at the right price.

Now if you had a fleet of 600 semi tractors and each takes 12 gallons, then testing the antifreeze to be sure you are getting your money's worth (maximizing life) would make sense.

But for one or two BMWs in the family just change it every two years.