brake bleeding poll

[swabbie]

OK..I'll bite that replacing ALL of the brake fluid could be worth it..especially if you have an ABS system..having owned vehicles for the past 44 years,I can't ever remember brake fluid replacement as a maintenance item..or have I just ignored it?

I have a 2009 camry XLE does toyota require it?

How many people here have EVER completely replaced the brake fluid in their bikes or cars..short of a major system failure..master cylinder or something?

Not trying to be a wise guy..just curious..if I'm behind the power curve I'd like to know..I keep my vehicles as long or longer than most..

Thanks in advance

[Daboo]

I've never replaced the brake fluid on any car I've owned in the last 30 or so years. I think I can remember doing it once way back in the 70's when I replaced a master cylinder on my 64 Buick Skylark. I tend to keep my cars awhile. Since then, the 83 Audi was sold in 95. The 84 Mazda was sold 16.5 years later. The 99 Camry is still running like a champ. And the 03 Outback was purchased used, so I don't know what the previous owners did. The shop may have bled the brakes when they changed brake pads, but it isn't required and I don't remember it being mentioned.

Chris

[LeDude]

It all depends on what kind of owner you are and what your priorities are when it comes to maintaining your ride.

I bleed my system every 24k miles or every two years whichever occurs first.

It's a simple job, takes about 15 minutes and in will help keep your brake lines in good condition over time.

do the math and see what makes sense for you

[Ralph M]

You can feel a difference, every 2 or 3 years I suck the fluid out of the
master cylinders then push the calipers right over to push the pistons back
and return as much as possible of the fluid to the master cylinders suck that
out I leave just enough to stop air getting into the system then top up pump
the brakes out and usually that does the trick without the need to bleed, I
know there must be a bit of old fluid still in there but it usually feels better
after. Bike systems can be notoriously hard systems to bleed due to the small
capacity of the master cylinder pistons not moving much fluid.

[NormanB]

Brake fluid is hygroscopic and over time absorbs significant moisture and that is why all vehicle manufacturers specify that the fluid should be replaced at some arbitrary periodicity, usually 24 months.

The water that is absorbed will under heavy braking (read high temperatures) change state to vapour and thus become compressible and effectively collapse your hydraulic pressure. On the assumption that you applied the brakes for a specific reason then the lack of response will come as a surprise and the outcome will be variable but probably unpleasant.

If you have never changed your brake fluid and not had an accident then congratulate yourself for saving money, perhaps if you carry pasengers that you cherish you should alert them to the risk that you are asking them to share in your ambition to die with money in the bank.

[InfernoST]

I have never done it on any of my cars but have done it on all of my bikes, it makes a noticeable difference in braking performance as does the fluid you use.

[Jetfixer]

Simple test. Bleed about three or four handle pulls out of each caliper. Compare the fluid you get out with the clean fluid you put in. I'll bet you decide to bleed your brakes more often.

[ErikDK]

A friend of mine, who is an auto mechanic, tells me that the brake cylinders and calipers last much longer since regular changing of brake fluid became common.

In the extremities of the system, the brake fluid is always the same, so it ends up with high water content and starts to corrode the pistons and bores.

Compared to the cost and hassle of changing components vs. fluid, I prefer changing the fluid regularly.

[Chet_Benson]

Never on a cycle and on my 89 Ford it got replaced when to the brakes were redone. I always figure if it is not broke do not try to fix it. You can spend all you time and money maintaining the cycle.

When i fix something that is not broken I get no satisfaction.

[JohnK]

The proverbial Murphy will bite you in the rear at the most inopportune time if you don't do the PM's properly or in a timely manner. Like others have said it's cheaper to change fluids,belts, hoses,etc. then it is to replace major components.

[swabbie]

I'm liking the idea of replacing the fluid.AS i said earlier., I do take other people's experiences and knowledge into account..I don't know it all..

Does the fluid in the master cylinders actually migrate down to the piston,or is it simply for resupply if a leak develops?I don't remember from my fluid power courses in the Navy..

Wouldn't seem to be too much effort with a bleed bottle to replace all/most of the fluid?

looks like my question was answered up above...

[MJR]

Brake fluid is hygroscopic and over time absorbs significant moisture and that is why all vehicle manufacturers specify that the fluid should be replaced at some arbitrary periodicity, usually 24 months.

Exactly and it's just one of the amazing things about DOT 3 or DOT 4 brake fluid. As it absorbs moisture, contains it, and controls corrosion at least until it reaches the saturation point and then corrosion will take hold. As it absorbs moisture the fluid begins to change color which is an indication of condition. Flushing period should depend on usage and level of color change. An ounce of prevention is worth a pound of cure as they say.

Does the fluid in the master cylinders actually migrate down to the piston,or is it simply for resupply if a leak develops?

Not sure about the level of circulation but the fluid does carry/share the absorbed moisture altogether.

[dalehazelton]

I change it on cycles when it get's yellow in the little window of the reservoir. I don't think I've ever done it in a car, but have had new fluid put in the system when I have to change calipers, which always rust severely on the outside here in snow country.

[Jetfixer]

There is virtually no fluid circulation in any disk brake system at the calipers. The master cylinder is just a plunger that you push by squeezing the brake handle. The plunger forces fluid pressure down the line to the caliper. The same fluid moves back and forth very slightly in the system. The quality of the fluid degrades over time due to absorbing moisture from the air and heat from the friction of the brakes. Clean fluid will be either clear or have a slight yellow color. Bleed your brakes and you will probably get black fluid out. A little time and effort and a relatively cheap bottle of new fluid will prevent major expense later. This applies to all disc brakes on any vehicle.

[dalehazelton]

Very old brake fluid will be red - and thick. I had to clean the master cylinder of my wife's Honda CM400 and it was really gunked up. New spring and plunger (although the old one cleaned up nicely in clean brake fluid) and running fresh fluid through hose. I didn't touch the caliper as it seemed fine. I was going to change the hose too and the owner of the cycle shop I picked up the rebuild kit from said that he has NEVER seen a brake hose failure in 35 years of working on old bikes, so I didn't.

[cliffyk]

Guess I'm odd man out (again)--I change all the "other" fluids, in all our vehicles, at least every 2 years. Motor oil is changed every 3000 miles/6 months.

My 1988 Kawasaki Vulcan had 230k+ miles on it, my '03 Mistang has 145k, the wife's '03 Highlander has 185k. The record holders were her '89 Celica that had 310k miles when we sold it, my '85 Corolla with 295k, and a 1990 Miata with over 325k miles--the new owner and his son drove it from here (Saint Augustine) to Deal's gap the day they picked it up and drove it another 50k after that.

They sent me this photo of it just after the engine blew in late 2010, four years after they bought it (probably didn't keep the oil clean):