changing brake fluid on a late model vehicle.

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I'm thinking about changing the brake fluid on my truck. What's the best way to go about changing it? I heard if you do it wrong you can mess up the abs pump.
 
Some ABS systems are tricky to flush. But fresh fluid will get into the ABS guy later.
But a good bleed can be achieved with a vacuum bleed. Easy and almost fool proof.
A Mity Vac or similar pump up vacuum tool, along with a hose, makes it a great job for a home boy.
KEEP YOUR RESERVOIR FILLED! A low reservoir can mess up all your good work.
 
Sciphi- Did you use a mityvac or something else? Ive been looking at it for a while, but I hear that it dosen't make good seals with the bleeder valve. Is that true?
 
So you can't bleed it like a non abs vehicle wear you just pump the brakes up and then crack the bleeder screw?
 
Originally Posted By: motor_oil_madman
So you can't bleed it like a non abs vehicle wear you just pump the brakes up and then crack the bleeder screw?

You can absolutely do it that way. It's just easier (and only requires one person) to get a Mitvac or similar tool. I'm a fan of the Motive Power Bleeder. The only way you can mess anything up with the ABS is if you get air in the lines anywhere between the master cylinder and the ABS pump.
 
That power bleeder is nice, I've had good success with using a mityvac and just making sure the reservoir is kept topped up.
My system is a bit overkill I guess, I do each wheel w/mityvac until the fluid comes out clean, then pump the brakes (bleeders closed of course). I then repeat at each wheel a few times with the mityvac, followed by a few minutes of gravity bleeding. Always ensuring the reservoir is kept full. A little hose on the end of the bleeder keeps fluid from dribbling all over the brake assembly.
I typically flush out the fluid every couple of years/30K miles more or less, always a very good firm pedal.
 
Originally Posted By: exranger06
Originally Posted By: motor_oil_madman
So you can't bleed it like a non abs vehicle wear you just pump the brakes up and then crack the bleeder screw?

You can absolutely do it that way. It's just easier (and only requires one person) to get a Mitvac or similar tool. I'm a fan of the Motive Power Bleeder. The only way you can mess anything up with the ABS is if you get air in the lines anywhere between the master cylinder and the ABS pump.


I'm going to have a buddy help me so i'll just do it this way. How do you get air in the lines between the abs and master cylinder? Will that only happen if I don't keep the reservoir filled up while bleeding?
 
Euro cars have a standardized reservoir cap that accepts a pressurized bleeder/flush tool.

Fill up the tank with DOT4, screw it on, pump it to 15 psi, open the bleeders one at a time, done flushing in 20 minutes.
 
I ended up buying a Motive pressure bleeder and was really excited to use it on my 07 Civic. Honda's got their own special reservoir cap, not a screw-on, and I had to use the "universal" one with a chain that you tighten under the reservoir. On this particular car, the reservoir is remote from the master cylinder and I couldn't get the cap tight enough to hold pressure. Ended up just waiting for the wife to get home and doing a 2 person standard bleed.

I'm thinking of just getting a Mityvac because it seems more universally applicable.
 
Originally Posted By: SteveSRT8
Gravity bleed. Easy and simple, but won't work on all cars, just most.
This is the easiest trouble free way to bleed. It just takes a little longer.

Google it, there is probably something on youtube for gravity bleeding.

I think on my car they started dripping out clear fluid at a rate of 10 minutes per caliper.

You can't mess up the ABS pump if you don't touch it. nNormally brake fluid just bypass's through the ABS pump unless wheel lock up is detected & activated.

There is a relativlely very small amount of fluid in the ABS and will mix in to the fresh fluid when ABS becomes activated.
 
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^^^yessir, easy and hard to muck anything up.

If you take the car out and use that abs a bit it'll mix everything up really fast! Then you can come back to the garage and let her bleed a bit more if you want.

I just do a gravity bleed almost every time I have a brake repair. I haven't replaced much of anything except pads and an occasional set of rotors in a loooooong time.
 
Wouldn't you get more junk if any out of the lines by pumping it instead since that would cause it to be forced out more.
 
I never had success with the vacuum pumps. Air gets in through the bleeder threads and prevents vacuum from forming.

I do the gravity way. Note that if you have air in your system, this will not work. This method is slow but how slow depends on the difference in height between your MC and the calipers
 
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so how does the gravity bleed work? You just open all the bleeder screws and let it drain and keep the reservoir filled? You don't get air in the lines by doing this?
 
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I used to use a pneumatic Vacula or some similar, but would sometimes pull in air around the bleed screw threads. Now I use a motive bleeder and love it. The only problem is if the seal isn't great at the master it can pump/dump brake fluid everywhere.

The old pedal method works great if you have two people.
 
I have no patience waiting all day for a gravity flush, no luck with vacuum and no-one to help out. I've been installed a tube fitting in the MC cap on all my recent cars. I just attach a small electric air pump regulated to around 5 psi and keep the reservoir full. When not in use, a vinyl cap covers the fitting, which is simply a 4mm Rivnut with a hole drilled though.
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