Brake Fluid Resevoir - Drain & Fill Effective ??

Wondering if a yearly or bi yearly Brake fluid Resevoir drain and fill (syphon out and fill) would be an effective 'freshening' alternative to bleeding? 2013 Camry ,2013 Corolla Here's additional thoughts / questions : 1. Could it introduce dangerous air bubbles by sucking out just the Resevoir with a turkey baster and refill? 2. Does the fluid actually mix ever between the lines and the Resevoir such that new fluid would mix with and refresh the old? 3. Related to #2 - if no real mixing occurs, does this mean that we actually drive thousands of mile on the same fluid trapped just in those lines from the factory!? If so, why even have such sized reservoirs? I've never seen a car even with thin brakes draw in much additional fluid from the Resevoir.
 
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Montreal, QC, Canada
It will help for sure. But you should gravity bleed a bit as well to remove water and copper that settles to the lowest point in the system: the Calipers and the Wheel Cylinders. Gravity bleeding is very easy to do, the hardest part is to put the car on jack stands and have the wheels off.
 
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Texas
It would take a LONG time for the fresh fluid to diffuse its way all the way back to the rear wheel cylinders. Brake fluid doesn't circulate to the wheels, just pushes out on braking, and flows back to the MC on release, so the fluid in the lines just shuttles a couple inches back and forth. True bleeding is much better after you've siphoned and re-filled the MC, but as others have said keeping the fluid in the MC fresh is better than nothing. Especially since the ABS/traction/stability pumps do circulate that fresh fluid through themselves.
 
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Virginia
Changing out the brake fluid does make a difference from removing moisture that causes the fluid to boil and leads to brake fade. As Falken said, allow the new fluid to purge the lines for best results. Its good practice to do this every 30K or so. Pumping the brake a few times will mix the new fluid with old fluid in the master cylinder, make sure the cap is on. Suck out the reservoir again for a more complete fluid change before allowing the lines to leak.
 

SumpChump

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Ah, so A. Bleeding is best B. Resevoir refill is ok (helps abs stay clean and disperses with old fluid a LITTLE?) ****** C. Pumping brakes DOES mix fluid. .... Or is this a point of disagreement? One post mentions fluid movin just a few inches the other post implies some actual mixing of some kind About 'gravity bleed'. I'm a dunce on that. Is tha just another term for 'pumping the brakes with a helper and closing the bleeder valve on the down stroke after a pump of clean fluid is seen? Or does it litersll mean to just open the bleeder at the wheel and let her drip without pressure or vacuum? Thanks!
 
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Paradise of Florida
Bleeding is the only way to get the air out. If no air isssue, then siphon refill whenever you want. 1. Does not introduce air bubbles. 2. It definitely mixes. 3. Most drive until a failure occurs. MC level does drop as pads wear. Brake labor and parts are expensive. Brake bleed every year or two, and at every brake service, to extend component life. Moisture accumulation percentage can be reduced and spent additives can be refreshed, with a MC refill.
 
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Moisture gets into brake fluid, and the vented MC cap is where it does it. But actually exercising your bleeder screws will keep them from rusting shut. Get over your intimidation and do it right.
 

SumpChump

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Originally Posted By: eljefino
Moisture gets into brake fluid, and the vented MC cap is where it does it. But actually exercising your bleeder screws will keep them from rusting shut. Get over your intimidation and do it right.
Man, this is what I love about BITOG! Although I do have valid fear since the nearest Toyota dealer is 1 hour away and if I mess up.... The ol lady will kill me to have it towed anywhere.
 
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Originally Posted By: eljefino
Moisture gets into brake fluid, and the vented MC cap is where it does it. But actually exercising your bleeder screws will keep them from rusting shut. Get over your intimidation and do it right.
maybe some, but the moisture builds up from condensation from temperature changes of the fluid during use. I always siphon and refill, drive and repeat...wait a week and repeat (give or take)...every other year BUT you guys are saying: 1) siphon 2) refill 3) open bleeders 4) until new fluid comes out of the bleeders 5) refill MC as needed to avoid running empty during process ??
 
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One Step Beyond
My 2 cents: 1) No air bubbles when turkey baster reservoir. 2) New fluid mixing is very slow as to not mean anything. 3) Could be a measure of safety. My Ford Ranger has ABS brakes. From the reservoir, the brake lines go to the ABS Solonide, then to each wheel. Each Winter, I will turkey baster the reservoir, then drive in a snow covered parking lot. Apply the brakes so that ABS is activated. This I hope will exchange dirty fluid for clean (in the ABS Selonide). Then, once again turkey baster the reservoir. Doing that along with a total flush every 2 years is the best I can do. Before my BITOG days, my brake fluid in the reservoir was 'black' Never again.
 
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North Coast
Originally Posted By: SumpChump
Wondering if a yearly or bi yearly Brake fluid Resevoir drain and fill (syphon out and fill) would be an effective 'freshening' alternative to bleeding?
No. brake fluid doesn't circulate through the system.
 
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6,170
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North Coast
Originally Posted By: SumpChump
Originally Posted By: eljefino
Moisture gets into brake fluid, and the vented MC cap is where it does it. But actually exercising your bleeder screws will keep them from rusting shut. Get over your intimidation and do it right.
Man, this is what I love about BITOG! Although I do have valid fear since the nearest Toyota dealer is 1 hour away and if I mess up.... The ol lady will kill me to have it towed anywhere.
Toyotas are super easy to bleed. Just put a little PB blaster on the bleeder and let sit for an hour. Then have the wife pump the pedal. As long as you keep the reservoir full you are fine. You only need to bleed them at every pad reline and the calipers will last at least 150k.
 
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North Coast
Originally Posted By: SumpChump
I wonder if the little ABS selenoid 'buzz' tests that most modern cars do shortly after going into gear moves any 'real amount' of brake fluid. Thoughts?
None. Not necessary unless you are a 120% anal retentive type.
 
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6,170
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One tip on your Toyotas...find out if they have an electric proportioning pump going to the rear wheels. If so you need to bleed with the ignition key on so the pump is activated. If you are unsure..just bleed with the ignition on.
 
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Canada
Originally Posted By: SumpChump
Do you know if on a toyota if I have to close the bleeder on each up rebound stroke of the pedal?
ugh... maybe you should take this to a professional. Not to be mean, but you clearly don't really seem to understand the basic principles of how your hydraulic system works. ALL cars you'd have to close the valve between each depression of the brake pedal, or else you'll get your lines full of air bubbles.
 
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Northern Kentucky
Also don't push the pedal all the way to the floor when bleeding, a block of wood behind the brake pedal can help with this. Something like a piece of a 2x4 will do the job.
 
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