Brake Flush @ 53k miles

Property of some reddit post which explains.

DOT 3, DOT 4, and DOT 5.1 are all glycol-ether based.
Glycol based fluids are hygroscopic which means they absorb water/moisture from the environment at normal atmospheric pressures at a rate of 2-3% per year. This process is exasperated in more humid conditions and climates.

This water content finds it's way into the brake fluid via microscopic pores in brake hoses, seals, joints and seams. As we've learnt, water mixed with DOT fluid has an adverse effect on the brake fluid by reducing it's boiling temperature and therefore reducing it's performance.


A benefit sometimes is to get dot 5.1 which has higheest boiling temp of the three if I remember correctly. I.e. it may also degrade just a bit slower. The only one I have used,tried in the past was Motul 5.1 and it was great.
 
DOT 4 has a higher boiling point than DOT 3, but absorbs moisture faster. For normal street use DOT 3 is recommended.

I just flushed the brakes on my Integra and figured out an easy one-man method. I used just a piece of clear tubing attached to a drink bottle with a hole in the cap and some fluid inside. Then I set it up on each brake caliper and pointed my GoPro Hero 4 camera with wi-fi towards the bleeder valve and hose, and used my phone as a video monitor while sitting inside the car and pushing the brake fluid out with the pedal. It worked like a charm, and I had all the brakes flushed and bled in about 15 minutes after getting the wheels off. I was amazed how each and mess-free the whole process was. Only thing I had to clean up with a slight dribble of brake fluid that came out around the bleed screw threads.

I tried a pneumatic vacuum bleeder and it was absolutely awful. Hand vac bleeder wasn't much better. I will be doing it this way with my GoPro from now on.

50762780_1307178599422433_1000909706432925361_n.jpg
 
DOT 4 has a higher boiling point than DOT 3, but absorbs moisture faster. For normal street use DOT 3 is recommended.

I just flushed the brakes on my Integra and figured out an easy one-man method. I used just a piece of clear tubing attached to a drink bottle with a hole in the cap and some fluid inside. Then I set it up on each brake caliper and pointed my GoPro Hero 4 camera with wi-fi towards the bleeder valve and hose, and used my phone as a video monitor while sitting inside the car and pushing the brake fluid out with the pedal. It worked like a charm, and I had all the brakes flushed and bled in about 15 minutes after getting the wheels off. I was amazed how each and mess-free the whole process was. Only thing I had to clean up with a slight dribble of brake fluid that came out around the bleed screw threads.

I tried a pneumatic vacuum bleeder and it was absolutely awful. Hand vac bleeder wasn't much better. I will be doing it this way with my GoPro from now on.

50762780_1307178599422433_1000909706432925361_n.jpg
Thanks for sharing your experience. Did you do one at a time while bleeding, right? I did 2-man-method brake fluid flush on my 1998 Honda CR-V with 183K miles for the first time not long ago. One problem I had was finding a right sized clear plastic tube for bleeding. Since the tube is not as flexible as rubber tube, sometimes it'd dislodge from bleeder valve by itself. And one of the bleeding valve had seepage problem afterwards.

I noticed all vehicles I've seen are always recommending DOT3 brake fluid by manufactures. Some even warned against DOT4 brake fluid as it may cause corrosion issues. And mixing DO3 and DOT4 brake fluid is not a good idea either.
 
I have been using 5.1 on few 20 year old cars without any issues. but as always your mileage may vary.
I have no idea why manufacturers keep suggesting dot3.
 
I have been using 5.1 on few 20 year old cars without any issues. but as always your mileage may vary.
I have no idea why manufacturers keep suggesting dot3.

DOT 4 is just fine for passenger cars. DOT 5.1 just has a higher boiling point is all, basically. DOT 5 won't work with ABS. DOT 4 is cheaper, so meh.
 
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Usually the fluids with higher boiling points (good for racing) also absorb moisture faster. That's why manufacturers keep recommending DOT3. For street use anything more than DOT3 is not necessary. You can use it, but you just have to be more diligent about flushing it regularly. I've heard of guys who track their street vehicles that they flush fluid for each event, switching from DOT3 to DOT4 for the track, then flushing it back out again to DOT3 after the event is done.
 
Thanks for sharing your experience. Did you do one at a time while bleeding, right? I did 2-man-method brake fluid flush on my 1998 Honda CR-V with 183K miles for the first time not long ago. One problem I had was finding a right sized clear plastic tube for bleeding. Since the tube is not as flexible as rubber tube, sometimes it'd dislodge from bleeder valve by itself. And one of the bleeding valve had seepage problem afterwards.

I noticed all vehicles I've seen are always recommending DOT3 brake fluid by manufactures. Some even warned against DOT4 brake fluid as it may cause corrosion issues. And mixing DO3 and DOT4 brake fluid is not a good idea either.

Yes, one at a time. It was super easy. I'm not sure where I got that tube shown in the pic, it may have come with the Mighty-Vac hand vacuum pump set. But it works great on the Integra bleeders, and I would assume it would work on the CX5 although I haven't tried it yet. One thing I learned is that it's best for the tube to come upwards out of bleed valve to a higher spot before turning back down into the container, to make it easier for air bubble to escape without going back into the caliper.
 
I will post if I hear about it before someone else.

Makes process so clean, convenient and easy to do by one person.

I'm swapping my front brake pads and hardware tomorrow so flush will finish this maintenance task for a while.

What about Motive's 1199 custom adapter? https://www.motiveproducts.com/collections/adapters/products/1199-custom-adapter-send-us-your-cap
It says they will take a customer supplied brake fluid reservoir cap and modify it for use with their tanks for $25.

I already have the Motive tank and catch bottles, so I am thinking of ordering an extra cap for my CX5 and sending it to them.
 
How can we understand that it is original brake fluid?

Do you mean on a used car that you purchased how do you determine if its original? It wouldn't necessarily matter IMO. If you've owned your car 2-3 years and you haven't changed the brake fluid, its likely due to for a change even if it were replaced just before you purchased it. You can get a brake fluid tester on Amazon. The reliability of these testers is arguable but my $8 tester seems to work fine. Tests 0% on new fluid and is testing 1% on 1-2 year old fluid.

If you want to get one and test yours and the water level tests at 2% or greater" change the fluid regardless of whether or not its original. If you've owned the car for 3 or more years without a brake fluid flush just go ahead and get it changed without testing it. It's likely already got too much water in it.
 
on a used car, one should replace all fluids just to be safe

also, check the date codes of the tires and replace if older than 6 years, no matter how much tread is left

- if the vehicle is older than 15-20 years, replace all rubber brake hoses with new rubber; and replace all rubber fuel hoses with new rubber one that rated for Ethanol mixes (10-15% depending on your gas)

Motive's device is simply a more costly version of something you can easily build from a garden sprayer for about $15 or less
 
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