TL_Captain

This is probably a dumb question for mechanical gurus. Can we apply the transmission oil drain/fill (3 times) method to brake fluids?

I don't have the knowledge to bleed/flush brake fluid. Would it be ok to use a syringe to suck brake fluid from the reservoir and fill multiple times?

Thanks

WDPanda

No, you have to bleed brakes from the calipers. No other way to do it.

ff4930

There is lot of videos online that show you how to do it.

TL_Captain

Thanks for the reply. Now I'm just curious. Why can't we apply the drain/fill method to brake fluid? I know the fluid won't be 100% fresh doing this, but it should be better than not doing anything at all, right?

TL_Captain

Thank you. I wish I could do this. They don't allow anyone to do auto works in the parking lot here. sigh~

gnuts

iTrader: (1)

I just watch a bobstheoilguy video and he says most of the fluid is in the reservoir and that his old coworkers used to just turkey baster out the fluid in there and put new stuff in. But he also didn't recommend doing that.

TacoBello

because it's a hydraulic system. Hydraulic systems work in such a fashion that a hydraulic fluid is incompressible. So, whatever is in the brake line, likely will never change. The fluid never circulates. So while the reservoir looks nice and clean, you still have junk fluid in your lines, which is a no no.

as that video points out, doing a brake flush is rather simple. I used to always be afraid to touch my brakes (my old man kept telling me I'd kill myself... Thanks dad ) but once you do one wheel, you'll realize how easy it is.

just a few things to note:
1.always use a brand new bottle of brake fluid. Once opened, the fluid starts absorbing moisture from the air. Old fluid is no good.

2. All you need is a 10mm wrench (I believe), a pop bottle, some flexible rubber hose (1/4" diameter, about 2-3 feet in length, from Home Depot) and clean fluid. That's it.

3. The hardest part is getting your wheels off. If you can handle that, you can flush your lines.

4. The only words of caution- don't let air get into the line- if you do, you just have to flush the bubbles out, and, there is a correct method of which wheel order you're supposed to do. I don't remember the pattern off the top of my head, but I know it is around AZ, or someone else can chime in on it.

Try it! You'll learn a bunch and you really can't screw up if you take your time!

ff4930

Can you do it in a friends driveway? Otherwise is best to go to a mechanic and pay for them to flush your brakes. It shouldn't be that expensive.

Also, before you even think you need one - get this - https://www.amazon.com/Brake-Fluid-T...e+fluid+tester
Maybe you dont need one yet!

Boosejars

iTrader: (1)

i flush my brake systems once a year - the best way is like mentioned above, get a turkey baster and suck out whats in the reservoir, add new fluid and then get to pumping. It's easiest to have a friend helping - they can pump the brake pedal and add more fluid so the reservoir doesn't run dry and you can go from caliper to caliper, best to take a clear container with a flexible hose on the bleeder valve, and some of the old fluid in the bottom of the container, pump until you see the new fluid mixing with the old, close the bleeder and hit the next. The brake fluid is hygroscopic in nature - so overtime it will absorb water bringing down the boiling point and also make it easier to compress. Easy enough to do-it-yourself.

thoiboi

I ask myself this:

Has it been 3 years since I last flushed my brake fluid?

If Yes: time to flush.

If no: wait until 3 years then go back to question.

The brake fluid tester is a bit excessive IMO.

TacoBello

Brake fluid can turn to shit much sooner than 3 years. Depends on driving habits and how often that fluid gets hot, as well as how hot it gets. For example, I'd change it after one track day, personally.

thoiboi

Of course, my advice is tailored toward the more 'general audience'


you know, the ones that create a thread online because they don't know how to drain and fill


If you're tracking your car, you better damn well know to take extra precautions on it