If you fellows are not smart enough to change your brake fluid and
most certianly you are not qualified to change it... and for you the best
and most safest way for you is to use the turkey baster... believe it or not
the fluid circulates within your brake system. and when you use the turkey baster and suck out your resivor you are changing about 60% of the fluid so if you do that 3 or 4 times eventually your fluid is changed.

But you fellows here that are discussing this you should not be cracking into your brake system especially if you have a newer car with abs... you should use a large C clamp to push the piston back and replace the pads and you should use the turkey baster....

Your life and your families life depends on those brakes and just the fact that you have to ask how to do it makes you unqualified to change the fluid..

There is a million other things you can do to your car rather than mess with the brakes....next time you get the urge to change your brake fluid go wash the under side of the car.

for you arthur,
even though a brake system is a closed system the fluid circulates.
thats why your fluid is dark because the fluid circulates even in a closed system. Its called fluid dynamics.

some good points.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

No , it is called fluid diffusion..
..and you can Turkey baster the res fluid every day for a year and the crap fluid in the calipers will still be trapped in the calipers . It does not RECIRCULATE anywhere. That is why you change it .
Anyone who has changed fluid knows you open the bleeders and push out the old fluid with the new .. that is where the new fluid in the res. comes into play.

That is why Used Car guys use a turkey baster... so you see nice , new fluid in the res., but quess what is still in the calipers and brake lines ...yup... the crappy,old, hygroscopic contaminated brake fluid.

A Turkey Baster is for 'Guys who are not Smart enough to know how to change there fluid'"????
That is some Excellent DIYer advice , that's for sure...............
Give me a break....

no matter how you bleed your brakes you want to start out with fresh fluid in the reservoir. I use a Mityvac extraction pump to empty my reservoir.

Also, you'll notice an opaque plastic cover over the reservoir of new Mercedes models. This is a UV shield, so I've been told.

Wouldn't the reservoir and MC and ABS module see some exchange of fluid even if the remote line near the caliper saw no change? If they did see some exchange wouldn't periodic removal of the reservoir fluid prolong the life of the ABS module and MC.

For the power steering pump, removal and replacement of reservoir fluid by vacuum is good practice. From what I've read. What do you think?

when the piston is pushed against caliper the fluid is compressed. and when the piston is released there is a fluid bubble in the resivor. take the cover off your resivor and have some one push the brake and watch the motion of the liquid. however slight there is circulation. now just use your turkey baster and change your fluid. brake fluid is very cheap so who cares about waisting brake fluid. My car is 24 years old and the brake fluid has never been changed even with the turkey baister... I will change tomorrow with the turkey baister and report back to you the color change... right now it looks like mudd.

I'm confused. What is the driving force that circulates fluid from the calipers back to the reservoir? The system has a dead end at each of the calipers. Last time I took Fluid Dynamics, fluids didn't circulate unless there was a flow path and a pressure difference. Replacing the reservoir fluid prior to bleeding the remainder of the system through the calipers may make sense to save time, but I've never bothered.

now your brake fluid becomes brown. where does the brown stuff come from. Down at the caliper. Even though there is only one pipe down to the caliper. IF you had a closed room of air would the air circulate yes, why because of heating and cooling. The air would rise and fall even though it is a closed room. Brake fluid is heated and cooled, It is compressed and uncompressed It circulates that why is is brown all over and not just at the bottom....

Here is a test for you... I had a professor who aruged that a car saved gas at 55mph vs 65mph.... do you think you save gas driving 55???

NO, because of the over drive transmission your car does 4000rpms at 55 and
3900 rpms at 65 so you use less gas at 65mph. Its the same with brake fluid. Inside that little tube when its compressed it is swirlling around in flows and eddies....believe it or not

Whatever it is you're smoking................keep it away from children.

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2007 C 230 Sport.

Brake fluid is designed to be almost completely incompressible. Any compressibility in the system would make the brakes spongy and could result in brake fade. This is what happens if you have air in the system, or if you have moisture in the fluid that can flash when heated in the caliper (due to not changing the fluid in 24 years). In reality, there is a very small amount of fluid movement from the reservoir into the brake lines when the brakes are pressed (how much does the reservoir level go down when the brakes are pressed?). When the brakes are released, this small amount returns to the reservoir. This is not circulation, this is a few CCs (at most) moving back and forth in the first few inches of the brake line. There is no driving force to get the vast majority of the fluid back to the reservoir.

Yes, changing the fluid in the reservoir will change the color of the fluid in the reservoir. However, it will do very little (or nothing) for the rest of the system.

Changing just the fluid in the reservoir is a complete waste of time.

Try a search for "Power Bleeder"

Someone here made one from a pump up sprayer and a pressure guage
(parts from Lowe's) Inexpensive!

All you do after you screw the M.C. cap of the "Bleeder" on to your M.C.
is release the bleeder screws at each wheel until you get clear clean fluid.

See the "Factory Manual" for your model!

changing the fluid in the resevoir does just that, and no more!

you must REPLACE all the fluid and then Bleed (proceedure is in the manual)

Let me tell my point over here:
My car has 195K and the brake fluid was never changed.
I did the "turkey pump job" 4 weeks ago, the fluid was brown( even had the impresion that the fluid tank is dark) but when I did put the new fluid in it was clear yellow. After two weeks the fuid un the tank was brownish again but not that bad as the first time. I did change it again with fresh fluid and is much cleaner now.
The point is that the temperature of the fuid in the calipers is way higher than in the engine compartment. So hot fuid goes up and colder one gets back to the caliper.Conclusion is the the fluid circulates ....

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New Addition to the family
2013 Passat TDI 5Miles
2004 E500 4MATIC Wagon 95k
1996 E300 Diesel 173k Sold
1993 300E 2.8 230k Sold
1994 E320 White Wagon 373K Sold
Still dreaming about ....500E


Radu Negru

Well, I've had enough fun. I'm going to take my turkey baster, a spatula, a couple of salad tongs, a meat thermometer, a garlic press and go adjust my valves.

some peoples minds just wont let them grasp certian concepts.

Your car only uses fuel on the piston down stroke. If your engine is doing 10,000 rpms you have that many explosions in the cylinder and if you car is doing 5000 rpms you have less explosions and you use less gas.


So if your in first gear and doing 10,000 rpms at 30 mph your using more fuel than if your in over drive doing 3500 rpms at 70 mph....


Air, in a closed room circulates because of heating and cooling... hot air rises. cool air falls....

brake fluid circulates, all be it slight, it circulates. because of compression and heating and cooling.... thats why your brake fluid is brown all over.

access your skill level... ???
If I wanted to change my brake fluid I would go out and loosen all 4 nipples and push the brake pedal....I would fill it up 3 or 4 times and push it again and again.....then i would bleed the brakes the old fashioned way and go about my business...there is a new brake fluid out that is 40 dollars a bottle your probably ought to go get that stuff....