Just curious, how is European distilled water different from distilled water here in the US?

I always thought the distillation process removed all the minerals and impurities.

Side note, if I were going to do a coolant flush/fill on my 3.0, whats the best way to do it without dropping the aluminum reinforcement pan? Or is that a must?

EDIT: I see that its probably imperative to do so.

I've always just opened the bottom of the radiator drain, or the lower hose if the drain is not accessible. Let it drain as much as will come out into a receptacle (or the floor if not eco friendly). Then run water through the vehicle while it's running with the radiator drain (or lower hose) open. When the only thing draining out is nice and clear I'll stop adding water and let the car run to clear out as much water as possible without letting the vehicle overheat obviously. Then I close the drain/hose and add coolant and water mix to begin the bleeding process.

The above is obviously not the most scientific way to do it, but it's always worked for me on all my m54 vehicles... and other engines BMW engines.

Marketing Hype!!!

Same marketing hype for European cars versus American cars. :rofl::rofl::rofl:

BMW coolant has a G-48 classification that specifically isn't harmful to the many composite components that make up the cooling system. Zerex, which is a G-05, comes close. Since the $ difference isn't all that much between the two I always have used the BMW brand. And you can't go wrong with theirs.

^Thanks man I'll have to crawl around under the X this weekend and see what is more accessible, it would be nice to just be able to crack the radiator drain and add distilled through the system and drain as much as possible, then just fill with 50/50 mix.

No problem. I think I've only actually used the block drain on a bimmer once and that was just because it was really easy to access on the m20 in an e30. You should be able to get a fairly thorough flush with the method I described... as I said, always works for me. :thumbup:

Edit: On some BMW rads (most I think) the drain is plastic... so be prepared to make sure you can source a replacement if it cracks/breaks.

As long as the mixed coolants are both listed for your vehicle, mixing is not a problem. Depending on the mix you can increase or decrease the amount of rust inhibitor. Mixing colors just makes a different color, no harm done.

I've stayed with the BMW coolant, making sure not to exceed 7 years or 150,000 miles before doing a complete flush and replacing all hoses and the expansion tank. Anytime the system is opened for other service such as a thermostat replacement, it's always topped off with the BMW product. The only additive used is one bottle of Redline "Water Wetter" at each flush. So far, I'm still on the original radiator and the original water pump went 262,000 miles.

2002 X5 3.0 289,200 miles
2004 325i 123,000 miles