Brake or hydraulic, fluid is a key part of the braking system, and a vehicle would not be able to stop without it — at least not by pressing the brake pedal.
As a BMW owner, you will already be aware of the importance of properly maintaining your vehicle, but it can be easy to overlook something like the brake fluid since a lot of drivers simply aren’t informed about it.
It pays to be aware of this essential ingredient that keeps your BMW running safely, so continue reading to learn more with our list of questions and answers covering the essentials of brake fluid.
How Often Should BMW Brake Fluid Be Changed?
BMW brake fluid should be changed every two years.
Over time, brake fluid absorbs moisture from the air, reducing its boiling point.
A high boiling point is significant because lots of heat is produced through friction during braking, and if this makes the brake fluid hit its boiling point, it will be vaporized and can lead to complete brake failure.
However, reduced boiling point aside, high moisture content can also cause corrosion within the car’s brake lines.
Hopefully, these points highlight just how important it is to change your brake fluid regularly in order to ensure the reliability of your brakes.
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How Do I Know if My BMW Needs Brake Fluid?
You’ll know if your BMW needs brake fluid because your car will display a warning light on the dashboard if the fluid isn’t changed at the recommended interval.
Newer BMWs are equipped with this handy feature, but if yours is an older model there are other signs to look out for which can indicate that it’s time for a fluid replacement.
These can include greater difficulty in getting your BMW to stop and unresponsive brakes after pushing the pedal, so if you notice either of these it is worth taking your car to a mechanic to get it checked out.
Can BMW Take Any Brake Fluid?
BMWs don’t require a specific, BMW-only specialized brake fluid, but they can’t take any old brake fluid.
There are different types of brake fluid and all are assigned a DOT number according to their properties.
In a nutshell, brake fluid with a higher DOT number will have a higher boiling point.
Brake fluid for a BMW should be rated as DOT 4, DOT 5, or DOT 5.1, and should be of normal or low viscosity.
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How Much Is BMW Brake Fluid?
There are a few different suitable types of brake fluid for a BMW, but you can buy 12 ounces of DOT 4 fluid for 6-8 dollars, and a gallon for between 25 and 28 dollars.
DOT 5 brake fluid is going to set you back a bit more because it is generally used in high-performance vehicles due to its higher boiling point. For example, a 12-ounce bottle on one website costs over 14 dollars.
While the DOT 5 rating sounds attractive if you like driving fast, it is unlikely that your car will need it.
Check your BMW’s manual to see what type of brake fluid your car requires before making a decision on which to buy.
How Much Does It Cost To Change BMW Brake Fluid?
You can expect to pay anywhere between 100 and 200 dollars to have your BMW brake fluid changed, with the price likely to fluctuate depending on the model of your car as well as your location.
For instance, it is possible to find an estimate of $114 for changing a 2006 BMW M5’s fluid, but this rises to almost $148 for a 2016 BMW 328i.
It is advisable to have your brake fluid changed by a professional rather than doing it yourself since the fluid is trickier to work with than other parts you might have changed yourself like the oil or wiper fluid.
Contact a mechanic near you for a more personalized estimate and enquire about a brake fluid change.
What Happens if You Don’t Change Your BMW’s Brake Fluid?
If you don’t change your BMW’s brake fluid it will lose effectiveness as it absorbs moisture, leading to a risk of brake failure and corrosion of the brake lines.
Changing the brake fluid at the proper intervals is also important to prevent debris from building up in the braking system, which could also affect your car’s ability to brake effectively if allowed to accumulate.
Is a BMW Brake Fluid Service Necessary?
Yes, a BMW brake fluid service is necessary.
Without servicing the brake fluid at the appropriate intervals, you run the risk of the brakes becoming less responsive and less effective — something that you don’t want to encounter unexpectedly while you’re driving.
If it’s the cost that’s putting you off getting the brake fluid serviced, it could wind up being far more expensive in the future to having a corroded brake system on your hands or, worse, the consequences of an unresponsive brake.
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What Color Is BMW Brake Fluid?
Most BMWs’ brake fluid will be colorless to amber, but some could be purple.
The difference comes down to what the brake fluid is made of, with silicone-based fluids required to be purple.
Only DOT 5-rated brake fluids are silicone-based, so this means that the other DOT categories (DOT 3, 4, and 5.1) should be transparent with a yellow tinge.
Can I Use DOT 3 Brake Fluid in My BMW?
Your BMW will still function if you use DOT 3 brake fluid in it, but it is not recommended and could be a safety concern.
In the long run, it will end up costing you way more money than the meager savings you would make by buying the slightly cheaper DOT 3 rather than the manufacturer-recommended DOT 4 fluid.
Money aside, you also want to ensure that you look after your BMW properly so there won’t be any nasty surprises along the way, such as the brakes not working as they should.
Is Pentosin Brake Fluid Good for a BMW?
Pentosin brake fluid is good for a BMW, as long as you use a low viscosity, DOT 4 fluid.
Pentosin is one of several brands of brake fluid but is an Original Equipment Manufacturer (OEM) to BMW for lots of fluids and chemicals.
So while the brake fluid isn’t designed specifically for BMWs, you can be confident that it will function effectively in your car’s system.
Can BMWs Take Any Brake Fluid?
BMWs can’t take any type of brake fluid: usually, they require a low viscosity, DOT 4 brake fluid, but in certain situations (for example, when racing on the track) it is possible to use a DOT 5 or DOT 5.1-rated brake fluid.
The brand of the brake fluid doesn’t matter so much, as long as the fluid’s DOT rating is appropriate.
How Long Does BMW Brake Fluid Last?
BMW brake fluid should be changed every two years once it is being used inside the car, but an unopened, sealed bottle of brake fluid will last indefinitely.
Once the container is opened though, the liquid will take on moisture from the air and so will only be good for around a year.
How To Reset Brake Fluid Light on a BMW?
To reset the brake fluid light on a BMW, turn on the ignition (without starting the engine) and hold the “odometer reset” button near the speedometer until the oil or microfilter symbol is displayed.
This will get you to the service menu from where you can reset any service reminders, and from here keep pressing the “reset” button until you see the brake reservoir symbol — it should look like a circle with waves in the middle.
Once you see this symbol, press and hold the “reset” button for roughly five seconds until the message “Reset?” appears on the screen, then let go of the button and press and hold again for another five seconds.
You will know that the reset has been successful because the light should change color and the “Reset?” message will become “OK” or “Reset”.
Remember that you should only carry out this procedure after having had your brake fluid serviced.
Final Thoughts — BMW Brake Fluid
We hope that this article has made the world of BMW brake fluid clearer for you and has helped you to understand your BMW a little better.
Lots of drivers are unaware of the importance of brake fluid in a vehicle and so don’t adhere to the correct maintenance procedures, but now that you are more confident about the features and the correct usage of this little-known component, you’ll be able to keep your car in excellent shape.
Bear in mind that when it comes to servicing your brake fluid, it is best to get it done by a professional.
So if it has been two years or more since you changed your BMW’s brake fluid, it may be time to contact a local mechanic for a quote.