BMW F-series (and more) brake fluid replacement DIY

Foreward:

Full disclosure, my brake fluid was way overdue, like 2 years overdue but better late than never I guess… This was a very straight forward, a bit tedious but wasn’t bad at all. There are a few different ways to accomplish this. I asked a few friends/neighbors if they had a power bleeder but they all (literally) had the Harbor Freight brake bleeder kit. The Motive Power Brake bleeder felt like a cooler and easier to use piece of gear so I went that route. It’s about $25 more expensive but in the end, whatever, I like my toys.

Technical skill
Cost
Time commitment
PITA factor

Prerequisites:

All the tools I ended up using (jack not shown)
  • A Brake Bleeder: I used the Motive Power Brake Bleeder
    • Teflon tape only if you get the Motive above to seal up the hose it comes with
  • Brake Bleeder bottles: I used these from Motive
  • 32 oz. (~1 liter) DOT 4 brake fluid
    • I used what my local auto parts store had (see picture above) but NOTE: BMW calls for a low viscosity brake fluid. Looking up brake fluid brands/performance/differences seems very similar to looking up what kind of engine oil to use. If you want to stick with what BMW says here’s an Amazon link to your DOT 4 LV options. If I was currently auto-crossing (damn pandemic, and we lost our Auto-X site) I would have probably waited for a better name brand (Motul) at twice the price but for daily driving I think I’m ok.
  • 11mm open ended wrench (Here are your Amazon options)
  • 10mm Nut Driver or an adjustable wrench (for the cover under the engine, any wrench will do TBH, you could probably use your fingers)
  • A car jack (I use this Arcan, extra long/low profile jack, get’s way under my m-sport suspension car, just barely)
  • 17mm socket for taking the wheels off
    • Optional: 1/2″ Impact Wrench (I use this Ryobi, I’ve done at least 20 tire swaps with it with no issue)
  • 1/2″ Torque Wrench
  • Some type of manual fluid transfer tool

 

The steps:

WARNINGS! Read this!

Brake fluid is nasty stuff, I wore latex gloves whenever I my hands had a chance to get in contact. Be very very careful not to spill any on any painted surfaces on your car as it eat away at the paint. I used the good old PIG blankets any time there was a chance of a spill or drop.

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  1. Decide how you are going to tackle taking off all the wheels. I originally was going to put the car on 4 jack stands but decided against it and instead just jacked up a tire, did that brake, rinse and repeat.
  2. Pop your hood, and remove the drivers side compartment cover. There are 3 10mm plastic “ikea bolts” that take a quarter turn to unlock
  3. Under the cover above you will find your brake fluid reservoir. With a rag, wipe around the cap and remove the cap.
  4. Remove the screen inside the reservoir. Mine was a bit of a pain to get out, I ended up having to use a pick tool to pry out. Be careful if you use a tool, the screen is fragile. I used it against one of the below ribs so it wouldn’t rip the screen
  5. Suck out as much fluid as you can with your pipette, turkey baster, whatever. (Bonus points if you get your neighbor to do it for you! Thanks Dawit!!)
  6. When you’re done removing as much brake fluid from the reservoir as you can, connect your power bleeder
    If you are using the Motive Power bleeder click here to make sure it’s all setup and ready to go
  7. Repeat the following process on each brake.
    The order in which you bleed your brakes is always as far from the master cylinder as possible to the closest. On my car it’s below but this can vary by car, always look it up)

    1. Passenger Side Rear
    2. Driver Side Rear
    3. Passenger Side Front (Special note for M-Sport Brembo’s)
    4. Driver Side Front
  8. Remove the tire and locate your bleeder valve on your brakes which should be covered by a rubber dust cap thing.
  9. Pull up your cover, loop your bleeder bottle through your 11mm open ended wrench and attach the bleeder bottle to the bleeder valve.
  10. Loosen your bleeder valve until some brake fluid starts to flow out, I noticed it comes out SUPER slow which is why having your wrench looped through makes it easy to loosen more.
  11. Pay attention to the color of the fluid when it starts to come out, mine looked like olive oil, darkish yellow. Keep watching it and wait until you see the color change to the new brake fluid
    color. In my case it was an almost translucent yellow. I had a few little air bubbles but not many at all.
  12. Once you see the new fluid start to flow through, wait a few more seconds (up to you, I think I waited about 5-10 seconds) and then close the bleeder valve.
    How ISTA words it

    Completely flush brake system, rear.
    Connect tank ventilation line (1) with collecting vessel to
    vent valve on rear right brake caliper.
    Open bleeder valve and purge until clear, bubble-free
    brake fluid emerges.
    Close vent valve.
    Carry out the same procedure on the rear left wheel
    brake.

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  13. Tighten up the bleeder valve, check the pressure on your Brake bleeder (pump it back up if needed) and go back to step 7 for the remaining brakes.
  14. After bleeding all 4 brakes disconnect your Motive by loosening the cap where the pump handle is, slowly
  15. Remove the motive from the brake fluid reservoir (get your rag ready to catch any drips)
  16. Top off your brake reservoir with your now 3/4 empty bottle of brake fluid, fill it to the MAX line on the side of the reservoir. If it’s over the max line, use your pipette to draw some out
  17. Put that PITA screen back in, and replace your reservoir cap tightly
  18. Get into your car, with the engine off and pump the brakes a few times. It should get rock hard (that’s what she said) and not squish down at all after a few pumps. Hold it there for a few seconds and make sure it doesn’t squish down
  19. Check your brake fluid reservoir again after pumping the brakes when the car is off
  20. If you need to reset your service maintenance light you can use the following method, it’s super easy and I’ve switched to doing it this way rather than using Carly on my phone
    Reset Service Light Procedure

    1. Without pressing the brake/clutch, press the start/stop button
    2. Wait for the service reminder to disappear
    3. Press and hold the odometer reset button. You will notice your trip meter reset and then go back to the value it once was. Keep holding for a couple more seconds At this point, service values that can be reset will come up. Use the odometer reset button to scroll through the menu.
    4. At the value you want to reset, press and hold the odometer reset button. “Reset possible” will change to “Reset?”
    5. Press and hold odometer reset button again until value is reset
    6. Press the start/stop button to start car or turn off car

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Cost Breakdown & Conclusion

So even after investing almost $100 in tools/supplies needed just for this job, you’re still saving money on having the dealer do it. It’s super painless, and now that I’ve done it once just like every other project I could probably bang it out in less than an hour.

ItemCostNotes
Motive Brake Bleeder$52.99One time purchase
Motive Brake Bleeder Bottles$25.99One time purchase
Brake Fluid$12.99Consumable
TotalS91.97Rough Dealer Estimate: $125-200

Special note for M-Sport Brakes (Brembo’s)

If you have an M-sport model or any other model with “higher performance” brakes you may notice you have two brake bleeder valves on it. One towards outside of the wheel and one on the inside of the wheel. In this case you just follow the whole “furthest away from the master cylinder rule” and start with the outside bleeder valve, then the inside one.

M-Sport brakes with 2 bleeder valves. The open ended wrench wouldn’t fit on the outside bleeder valve

 

Setting up your Motive Power Bleeder

  1. Use some teflon tape on this connection. It’s known to be a little leaky and the manual even suggests using teflon on it
  2. Insert the rubber gasket that comes with the power bleeder into the female end cap, push it in so it sits flush
  3. Connect your empty power bleeder to your reservoir and pressurize it to 10-15 PSI (get ready to pump a lot) Leave it pressurized for a few minutes, listen for hisses, make sure you don’t lose any pressure
  4. Once you verify there are no leaks, depressurize it by slowly unscrewing the cap on the pump part of the power bleeder
  5. Add your brake fluid to the power bleeder. I used about 3/4 of a bottle of brake fluid, screw the pump thing back on and connect the other side to your reservoir.
  6. Pressurize the motive bleeder to 10-15 PSI, I went with 14 as I’ve read (and heard from a couple friends, you need to be careful not to over pressurize it)
    1. You should see brake fluid start to fill the tube
  7. Now go back to step 7 above.

 

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