Before I forget, Merv, I am sure I can get you a good price out of Sytner Cov. A bid closer to Stourbridge.

Dlevi, you're sure they use DOT5. I thought it was 4

 

You are right. Just checked it on TIS. For some reason, I thought the standard E60 used DOT 5, and M5 on DOT 4. My bad.

In which case, even more the reason for changing the fluid, as DOT 4 is ether-based and highly hygroscopic.

 

I did it. Brakes definitely felt firmer afterwards. I would do it again, wasn't too expensive - cost the equivalent of 70sterling in my country

 

I guess you don't really need to get it changed, but I would recommend to have the fluid change just to have it done. Try an independent shop for a cheaper price. Not sure if the dealer uses synthetic, but you can probably get synthetic for the same price at an outside shop.

BTW, after I had the service done, I didn't notice a difference.

 

You do need to have it changed. Brake fluid is hygroscopic - it soaks up water which then corrodes the brake system - not a good thing.
Not noticing any difference after it was changed is a good thing - it means you didn't leave it too late.

 

Having water in a fluid which, in its pure state, relies on its hydraulic properities for transmission of pressure does however reduce the hydraulic efficiency.

ABC

 

Coolant change every third year for BMW Nordic cars, not ever forth.
Coolant good for some -40 C or F.

DOT 4 (brake fluid) was what the BMW Service put in my car.

 

Not many people here work on their own cars, but it's really not that hard to do yourself. I have a pressure bleeder (cost about $50), so it's a one man job and only costs about $12 for high quality fluid. I will probably do it when I switch to summer wheels since it will take less than an hour. I don't think BMW would do it for free till next year. Wouldn't really matter for street driving, but to take your car on the track the brake fluid has to be less than 6 months old and there is a driving school in June I'm looking forward to!

 

My suggestion is to change the brake fluid. Its not that expensive regardless if you do it at the dealer or at a good independant shop. There are two reasons that affect the fluid:
1. Its hydroscopic and absorbs water
2. If you brake hard and excessively (it should only happen on the track) the fluid in the caliper can reach its boiling point and loose its effectiveness.

On a normally street driven car it shouldnt make much difference as you can try very hard to boil the fluid.

And finally, no it will not void your warranty if you dont change it. I am not sure where you are but here in the States it is covered by BMW for the fist 4yrs/50000m or 6yrs/100,000m if your car is a CPO.