Save money on your brake fluid, air filters and oil change by doing it yourself!

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Izzard

Member
Joined
Aug 10, 2019
Messages
7
My 2016 BMW i3 REx was recently due for its “big” service. I bought it here in the UK in the summer of 2019 when it had just turned three years old; almost certainly after finishing a lease. So this year (2020), it’s supposed to have its brake fluid and oil changed, as those are due every two years. This is a service for which the local BMW dealership wanted to charge me several hundred pounds. However, the car is out of warranty and I like to be self-sufficient, so I gathered the tools and information to do these jobs myself. Here’s what I learned and some of the costs I incurred.

I hope this is useful to others here. Please feel free to share on other i3 group/forums.
 
Thanks for the write up! I like the idea that I would do this, but living in Germany I know it would kill re-sale value if I didn't have the BMW stamp in the book. Well done to you though.
 
Thank you. Yes, I’m planning to keep mine for a long time rather than sell it. It’s worth considering though, you’re right.
 
Bertone said:
Great post!!

One question...how do you reset the service intervall indicator on the dash?

You hold the trip reset button on the left of the instrument cluster for several seconds and navigate through the “Reset?” options it presents. (Quick press for next, long press for select.)
 
Nice write-up. Thanks for sharing.

One question: Although I've done this many times on older vehicles I've never done it on one with Antilock Brackes. I've been told that you have to use a different procedure to cycle the ABS and ensure that you flush the old fluid out of the controller and the new fluid in. I didn't see anything about that in your write-up so am wondering if you did this or just flushed through what you could without cycling the ABS?
 
No I’ve not heard of that. Have you got a link that adds weight to that concern we can look at?
 
Izzard said:
No I’ve not heard of that. Have you got a link that adds weight to that concern we can look at?

You can Google it and find lots of references. Here's a quote from one:

"Power and pressure bleeders are changing along with the systems they service. In the past, only 15-30 psi was required to pressure-bleed the system. But some new ABS modulators with electronic brake proportioning may require 50-60 psi to bleed or flush the system. If you can’t get your pressure bleeder to work under these conditions, look at the service information for the required equipment or pressure setting.

On their own, gravity, manual or power bleeding methods can’t completely flush the volume of fluid that is in the ABS modulator. Inside the modulator, there might be as much as five ounces of dirty fluid after flushing. The only sure way to flush this fluid is to use a scan tool to actuate the valves in the hydraulic control unit. Be aware that the worst fluid is trapped in the ABS valves and passages due to their non-integral design."
 
Sorry I meant specifically in relation to the i3 but I understand what you’re saying. I do test the ABS as a matter of course after working on the brakes. That “actuates” them. Good enough for me (especially on a 3 year-old car).
 
Izzard said:
Sorry I meant specifically in relation to the i3 but I understand what you’re saying. I do test the ABS as a matter of course after working on the brakes. That “actuates” them. Good enough for me (especially on a 3 year-old car).

Here are few links for the procedure. The first is the i3, and the other links are generic BMW brake bleeding procedures. When I did my i3 I did not bother with running the DSC pump, no problem with brake feel afterwards.

https://www.newtis.info/tisv2/a/en/i01-i3-hat_201408/repair-manuals/34-brakes/34-00-braking-check-ventilation/1VnXrIyoHr
https://www.2addicts.com/forums/showthread.php?t=1588350
https://f30.bimmerpost.com/forums/showthread.php?t=1318401
https://www.m5board.com/threads/brake-bleeding-dis.450689/#post-5838225
 
The 'old' way of opening a bleeder and pushing the pedal to the floor, holding it while someone closes the bleeder is not the best way to do it in modern cars. You really do want to instead use a pressure bleeder system. If you push the pedal all the way to the floorboards, you'll be moving it beyond any normal range, and risk additional crud from getting in the system or seals that may then have issues. Typical day-to-day travel will keep the rods clean, but pushing it to the floorboards will likely try to push some crud in there.

FWIW, I bought a pressure bleeder from ECS Tuning awhile ago, but the cap they provide for my two BMWs would not make a good seal, and when the tank was pressurized, it leaked all out and on the vehicle...I do not know if they've changed the design. The bottle itself holds pressure fine, but it's the cap that you put on the reservoir that is (was?) the issue.
 
jadnashuanh said:
FWIW, I bought a pressure bleeder from ECS Tuning awhile ago, but the cap they provide for my two BMWs would not make a good seal, and when the tank was pressurized, it leaked all out and on the vehicle...I do not know if they've changed the design. The bottle itself holds pressure fine, but it's the cap that you put on the reservoir that is (was?) the issue.

Mine did that as well until I realized you need the thick rubber gasket that goes into the cap so it seals between the cap and fluid reservoir.
 
There are also bleed kits that work the other way around, by connecting to the bleed valve, generating a partial vacuum beyond the collection vessel and pulling the brake fluid down from the reservoir.
 
I have experimented with the gravity method, the two person brake pumping method and the vacuum pump method. All work ok. I prefer the two person method. We drive 20,000 to 30,000 km per year. A 3 year frequency is plenty for our style of driving. Bleeders seize after 3 years so are easily broken. Will try using silicone grease in the future as suggested by someone on this site. Never had an issue with ABS.
 
TOEd said:
We drive 20,000 to 30,000 km per year. A 3 year frequency is plenty for our style of driving.
Our 2014 i3 has been driven only 16k km total, yet its brake fluid has absorbed water from our typically humid air through the brake fluid reservoir cap's breather hole and maybe through the rubber walls of some of its brake lines. This would have occurred independent of the distance driven, so I question whether one's driving style affects the life of brake fluid with the exception of competition driving in which brake fluid could become quite hot.

Before the recommended 2-year replacement interval occurs, I plan to test the brake fluid to determine whether it has absorbed enough water to warrant being changed.
 
There are brake fluid test strips you can purchase. They can be quite illuminating as to the condition of your brake fluid. You can't go by looks. 2-year intervals is the safer choice to change it out. A caliper, or worse, the ABS device are not cheap not counting the potential safety factor. Depending on where you live, especially with the regen braking, you may never overheat things on a downhill run, but in general, lowering the boiling point isn't a great idea, nor is starting to rust things from the inside out!
 
Our driving style is as follows: we are retired so avoid driving in the rain/snow; we rarely use brakes (regenerative braking is sufficient) so braking system doesn't heat up and cool ie "breath"; car is stored in a garage (ie out of the weather).
 
The humidity in Toronto in the summer can be quite oppressive, depending on which way the wind blows! That part of Canada is fairly flat, so boiling your brake fluid is not a likely issue. The rubber components in the system will allow moisture to get into the brake fluid. Now, given all of that, would three years be a major risk, probably not...but especially if you can do this yourself, why not do it at the manufacturer's recommended TIME interval.

Some things in a vehicle are distance related, some are time related...brake fluid is more time related so even if the car was not driven, but just sat somewhere, it would still be a good idea to change the fluid.

As I mentioned, there are brake fluid test strips you can buy that will give you an idea of the current state of your brake fluid. If after two years, it tests fine, yeah, extend it a bit.
 
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