I noticed this while scanning the owner's manual, the other day, and I now have 33,000 miles on my RX, putting it past the recommended 30,000 miles for a brake fluid flush. While I used to flush brake fluid, years ago, I now leave that up to the pros. I'm just wondering what the cost will be. I also noticed that long life coolant isn't recommended to be changed for many, many miles. Personally, I don't think I want to wait more than 5 years.

Thoughts?

The TV mechanic on the show (I think it is ) "Motorweek) explained that it is important to flush the fluid because the fluid absorbs moisture ["hygroscopic,"].

When I first started driving no one that I know bothered with that stuff but I guess we have learned more about how cars work over the years.

That said I usually don't keep a car long enough to wear out the tires or battery but I do have two cars that I do intend of flushing out when I get the chance.

I bought a 62 Vette a few years ago that is in good condition but I intend on going over it from top to bottom and make it like new, and the 96 that I bought new has sat in storage in my garage while I was busy moving all over the country.

I just moved from NY to Anderson SC last August and just added a second two car garage and work shop. I am waiting for my lift that I ordered to arrive and when it does I definitely will flush the brakes. I have done brakes jobs in the past (come to think of it I haven't had a car long enough to wear out the brakes in a while) and bleed out the air after the break job. I doubt that it will be any harder to flush the system than it is to bleed the air you just use more fluid and make sure you do it in the proper order starting with the wheel closes to the master cylinder and working your way out.


If you intend on doing it yourself the money you save will more than pay for the cost of this tool



Here is a good article explaining why fluid should be changed

thank you for the brake fluid article, i am one of those who also never changed the brake fluid on my trucks, unless the brakes are in for service. I didnt let them do the $120 brake flush at the 30,000 mile service because i really didnt think it was necessary. I will have the fluid changed completely when the front brakes are in for service. I am at 36000 miles now and i dont think the brakes are going to make it to the 60 or 80 K we once hoped because of the type of system that is on the hybrid. Personally i am more concerned that the oil in the transmission be changed before 100K even though it is synthetic.

Regardless of what it costs to flush to brakes, keep in mind that it might be the ONLY money you spend on the braking system. Some reviews of hybrids have projected brake pads/discs to last the LIFE OF THE VEHICLE! Can't complain about that.

A lot depends on your driving habits. I seem to be able to make my brakes last forever even on normal cars before I started driving hybrids but I have always had the habit of watching the traffic and lights ahead and taking my foot of the gas long before I intend to stop. But I have been a passenger in many cars where the driver leaves their foot on the gas when the light ahead is red without even attempting to glide up to the light. Then at the last second with a few feet from the light they hit the brake hard. These people will burn through brakes reguardless of if they drive a regenerative braking system or not. The whole key to regen braking is a light touch on the pedal to allow the generator slow the car without the brake pads coming into play. If you put light pressure on the pedal almost 100% of the stopping will be accomplished by regen braking but if there is no anticipation and you hit the brakes hard at evey stop almost all the stopping will be by the brake pads. I have noticed a big diffrence in the regen braking between the RX400H (All wheel drive) and the GS450H. The RX did not slow down very much when you took your foot off the gas, but the GS regen kicks right in, it almost feels as if you downshifted to a lower gear the moment your foot comes off the gas. My guess is that with the more aggressive regen programing the brake pads won't really get much use at all [unless you had poor driving habits].

There is a long hill with a gradual down hill slope on the way to my house. With the RX I was able to turn on to the street at about 20 MPH and coast all the way to the bottom of the hill. But if I do the same thing with the GS I have to use a little battery power less than half way down the hill in order for me to get to the bottom. I guess for some reason the felt it was better to program more aggressive regen into the GS

I may be inept, but I have never liked the MityVac much for my cars or motorcycles, and actually gave mine away recently in lieu of more conventional bleeding methods. One that works pretty well is to force the brake fluid up from the calipers with a well-fitted syringe.

Now here comes the teasing...another method that I recently used on my Porsche 968, a rather difficult vehicle to bleed, is what I might call the successive dilution method. Brake fluid is quite cheap so I simply suck out as much fluid as possible from the master cylinder and refill it with fresh fluid, then drive the vehicle for a day, and do it again (and again). After about 6 drain/fills the fluid looks fresh and new.

Tom

i hear what your are saying, however based on t he wear measurements the 'technicians' take during my oil changes my brakes on the 400h are not going to make it to 60 or 80, more like 50K or less so it seems to me i will have the fluid changed at that time. i didnt see a reason for a $600 service bill at the dealer for the 30K visit. So i asked them to do what TOYOTA required at 30K and it came to $225.00 plus tax. They were not insistent on the brake service at all, only suggested it and i get the feeling most of their customers dont question their advice.

I have been working on cars for over 40 years both as a hobby and as a way of earning extra money to add to my real job pay check. And since I work alone in my garage with no extra foot to pump the pedal the Mity Vac is indispensable. I doubt that the fluid near the pads is clean. Try bleeding some out and check how clean it looks, I it will not be as clean as it is in the fluid master cylinder. I haven't worked on cars in a long time and I truly love getting dirty working on cars. That is why I can't wait to get my work shop set up in my new garage in my new house

Thanks for the links, Silver and everyone else for your comments.

I too, have done plenty of brake jobs on my 68 Corvette, from installing brake lines and calipers to a complete silicone fluid replacement. I've flushed by gravity, Mity-Vac, and venturi vacuum pump that used compressed air to generate vacuum. None worked as well as a professional pressure bleeder, but the nice apart about this ultimately messy job was that the silicone fluid was harmless to my painted garage floor, my hands, and the car. Maybe if I were retired and had tons of time n my hands, I'd buy one of those pressure bleeders, but right now, with work and other hobbies, I'll leave it up to the dealership.

By the way, Car & Driver estimated RX400h brake pad life at over 100,000 miles. I think the key to long life (as Silver mentioned) is to use momentum that our 4600 lb vehicle has. I coast as often as possible - it makes it easy to justify rocketing past those X5s and Cayennes!

Dave

From the dealer's hybrid specialist (though this flatly contradicts the 'overkill' maintenance scheduel) ... off the record, but still, from one who is as 'in-the-know' as one can possibly be:

http://priuschat.com/forums/care-maintenan...-you-don-t.html

So if you ARE paranoid, or have cash to throw around you can ... but it's nice to know you don't have to.

Thanks for the info!

Brake fluid, other than DOT5, is hygroscopic (absorbs water), and as such should definitely be changed on some sort of reasonable schedule, to avoid degradation of materials it is in contact with.

Tom

The comments in the link included this:



Still, aluminum can corrode if it had not been treated or had been insufficiently treated. Also, I'm not certain if the brake lines are stainless steel. I've never seen any corrode enough to leak, even in Connecticut.

I may have my brake fluid replaced once during the warranty period, primarily as added insurance.

Also if you do a lot of hard braking, [racing on the track or long descents down high steep mountain roads] the fluid temp can get very high, the water can boil and turn to steam. When that happens you can lose most if not all of the ability to brake.

Hugh? Brake fluid turn to steam? Brake fluid is oil ... so, no steam

I never said that, go back and read my first post which is post #2. I said fluid is hygroscopic, therefore if it is hygroscopic it contains`water, water will turn to steam when heated

Hygroscopic does not mean it contains water, it means it can easily absorb moisture. Brake fluid can not contain any moisture what so ever because that is what will degenerate your brake system. Now in racing and repeatedly hard braking when the brake fluid over heats then that miosture will turn to steam if there is any present, if not the brake fluid it self will boil at a much higher temp.

Thank you that waas the point I was trying to make

Your welcome

I've seen brake fluid from the calipers look much worse than fluid further up in the system. One method I've heard about and used is to open the bleed port in the caliper when changing the pads. This allows the old fluid to come out when the pistons are pushed back for the new pads. Then, when I've changed all the pads for that maintenance (both front and rears rarely need to be changed at the same time), I pull some additional fluid through the calipers and top off the system appropriately. I think the key item is that you never want to get contaminated fluid into the anti-lock brake mechanism, it would not be a simple repair if you ever had a fault.

Ever looked at the front calipers on your hybrid (much less, the rear)? We have over 70K miles on one of our hybrids. There's so much of the stopping power done by regenerative energy recapture, that literally the minimum wear ever takes place. Our front pad? You'd be hard pressed to even guess that they have 4K miles on 'em ... much less the rear pads. You'd really have to be doing tons of crazy-insane breaking to get pads to wear a lot, on a hybrid. In fact, the bigger problem for those who drive extra carefull in hybrids, is rust building up on the rotors. So I hit 'em hard ever so often, to keep the rust off ... just in case. As for fluid change, since the Toyota hybrid specialist confirms 100K miles is do-able. That's when we'll be doing the flush.

What he was saying is, the brake fluid can attract moisture (water) if any is present. So, if the system has managed to attract water, high temperatures can turn the water to steam. Not something you want. This has been a major concern with the newer brake fluids.

I'm looking ahead to the 30k service and want to be prepared for any dealer 'games.' What are dealers charging for the brake fluid flush? Might make sense to rent the appropriate tool and do it myself...


Fenton House

All that is needed is a transparent container, a length of tubing, a wrench, spare fluid, and a helper. Devices are available (i.e. tubing with a check valve) to eliminate the need for the helper. It is not at all difficult if you have a little experience working on automobiles.

I do have plenty of experience, but with a painted garage floor, I am wary of doing any more brake fluid flushes. Time is another issue for me now, as I'd rather not spend an afternoon doing it, myself.
But you are correct in that is not difficult as long as you bleed in the correct sequence.

Dave

I see you are in San Diego. Just had the 30,000 check done on a ES 330 at Bob Baker Toyota on Federal Ave. $230 including a discount coupon for the brake bleed that they had at the shop.

That's an interesting point, Dave. I am considering painting my garage floor, probably with epoxy. Isn't this impervious to brake fluid and other solvents?

Tom

Tom,

I believe it is, but you might want to check with the manufacturer to be sure. Brake fluid is very strong (can eat through polyurethane paint, from what I understand) stuff. Unfortunately, when my house was being built, the home-type epoxy floor coating kits were not very common and those companies that would do the whole job were asking an arm and leg for payment. Thus, I went with paint. Someday, though...............

Dave

Dave. I know more about DOT3 damaging paint than I wish to remember. I once had a car vandalized with DOT3--apartment neighbors jealous of my brand new car. It dissolved the paint right down to bare metal.

Tom

I'm being charged $599 for my 30K. service.

OUCH!



DOUBLE OUCH!

I know this is an old thread; I was searching for specific directions on brake bleeding and came upon this information in need of correction. Couldn't help myself.

Brake fluid is hygroscopic meaning it attracts water from other sources like the atmosphere. So it will eventually absorb water. Brake fluid gets hot; the water will vaporize (turn to steam) and give you a mushy pedal since vapor is compressible.

I have decided to have our fluid flushed when I take the RX in for that steering recall (which takes at least 7 hours, by the way). Our RX has approx. 41,000 miles on it.

I used to do this, myself, but the combination of working with a hazardous fluid and its effect upon a painted garage floor has convinced me to just let the dealership do it. The cost is just a bit over $100.