Went to dealership for Brake fluid flush/bleeding but not sign tires removed

on the internet, there are many things. i like to stick with the recommendation of the people who designed and built my car. ymmv.

 

Well, if its on the internet, it must be true. LOL.

 

some have set up cameras in their cars.

 

Thanks for this.

When setting invalid mode, you are pushing the power button twice without foot on the brake? The "ready" condition where the engine won't go on? And how does that go, say if you're 20~30 minutes doing the bleeding, it doesn't run the batteries down too much? Try to work quick?

I have a MightyVac, the hand pump vacuum device. Is it good to apply vacuum when bleeding, or not so important?

 

1) Brake fluid is hydraulic fluid, it is also hygroscopic. Over time, moisture diffuses into the fluid through brake hoses and rubber seals and eventually, it'll need to be replaced. Water in the brake system can form vapor pockets when the brake fluids get too hot, so when you are pressing on the brake pedal, even if it goes all the way down on the floor, the brakes still are not applied.
2) The brake fluid system isn't a vacuum system, it's open to air, that's how you're able to top off the fluids and for it to go through the brake lines.
3) Yes, brake fluids can be contaminated.
4) I wouldn't wait that long for a brake flush, it's recommended every 1-2 years.

Yes, when setting to the invalid mode you press the power button twice without stepping on the brake pedal so that the accessories are on and engine off. Your auxiliary battery will last longer than 20-30 minutes, so you don't need to worry about the battery being drained while doing the brake bleeding service. If you have a healthy auxiliary battery, it'll last for along time without the alternator recharging it. I would say around 1-2 hrs but I wouldn't want to risk draining the battery longer than.

As for the mightyvac, I have one and we just use the hose as a draining hose, you can have the vacuum on if you want, but I don't think its necessary since it'll just be like a conventional brake bleeding.

 

I'm pretty much in agreement with NutzAboutBolts, beside the time. I think 1-2 years is a bit soon, but it doesn't hurt. I would still do mine around the same intervals as ATF.

Before someone asks the obvious question of why don't we use DOT5 to raise the boiling point of the system and thus preventing water from forming vapor pocket, keep in mind DOT5 is silicone based and it does not absorb water (it doesn't prevent water from entering the system either). Water within the DOT5 system will be isolated and become steam when get hot. Overtime steam/moisture will cause rust inside brake components and might cause more expensive repair, or brake failure in the worst cases. DOT5 is more suitable for racing applications with more frequent changes.

 

How does moisture get in the system?

 

3 years or 30k miles.


iPhone ?

 

Since this has morphed into DIY thread, here's the Toyota instruction. Nutzaboutbolt's video is what turns the light bulb on tho.

 

Rubber hoses and seals are slightly permeable to water vapor in the atmosphere, so the hygroscopic fluid slowly absorbs some of the moisture. (Hypothetically, it would reach some equilibrium moisture content after infinite time, assuming constant humidity.) Also, fluid in the reservoir is exposed to a fresh batch of atmospheric air every time the fluid level drops when the pressurizing pump runs.

 

It's sad if you can't "trust" a mechanic to do what you paid them for, but it's not a hard thing to verify.

Put a clear drain hose on a bleed nipple. Energize the system and crack the valve open slightly (enough to let fluid come out). If it's not clear/light gold, it's contaminated and your line was not flushed with fresh fluid. You can't hide contaminated brake fluid in the line...it's quite obvious (dark brown or even gray). You should only need to check one caliper since they likely wouldn't bother to do one wheel correctly and leave the others undone.

 

No.

I do it all the time. I use a syringe to suck out as much brake fluid as I can from the master cylinder's resevoir. Then I fill will fresh fluid. This eliminates me mixing contaminated and fresh fluid in a big container and fresh fluid is immediately pumped through the brake lines as I flush out the system. Saves a lot of time.

 

I'd tread carefully with this: wouldn't you want to ensure it's in the "disable" mode (described by NutzAboutBolts above)? Otherwise you may get warning lights?

 

There might be more steps involved for the Prius, but you only need a couple inches of fluid in the hose to see if it's new or old.

Crack enough to let some out, immediately close.

 

That's common. The filter price is $20 and the smallest labor increment is I think 0.1 hour, or $13. Of course you can do it for less, but they've got a ton of overhead.

 

Well, I am trying to get everything I should get done on my upcoming 30K mile service on my 2015 Prius. I am basically following Toyota recommendation, but have decided to add ATF WS "drain-and-fill" on the list of things to be done based on the information found on this forum. Then I started thinking about brake fluid change. As it turns out, US version of scheduled maintenance log has no mentioning of brake fluid replacement, just visual inspection of brake line and hoses. I searched for Brake Fluid replacement in the forums and ended up in this discussion. So, does brake fluid need to be flushed and replaced at 30K mile or not? Why Toyota recommend this preventative service for Canadian owners and not for US?

 

Yeah, this is from the Canadian 2014 Owner's Manual Supplement, actually applicable to all Canadian Toyota vehicles. Don't know why. I couldn't resist clipping the whole thing, nice summary:



Again, @NutzAboutBolts video really helps. With the picture-in-picture showing the timing of pedal depression and open/close of bleed bolt on front calipers, for example.

 

As mentioned in your previous post on this thread, Honda has Brake Fluid Replacement on maintenance schedule every 3yrs regardless of miles. I have to admit that I haven't followed that schedule on our Civics faithfully, but I remembered. You wouldn't think there are difference in brake fluid between US and Canadian Prius? Since I have no place nor tools to DIY, I am planing to take my car to a shop for most of maintenance items on my 30K mile schedule. I will replace air filters myself, but oil and oil filter and ATF change are going to be left for a competent mechanics at shop to perform. No cost estimate yet, but I am hoping to get them done for less than $100 by providing oil and filter and ATF. Honda dealer charges $150 for brake fluid flush on Civic, and independent shop for the same service at $110. If I have to add brake fluid flush on to do item for Prius, what the cost should be?

 

As far as I've seen so far, the only person to actually put a test strip in his old brake fluid bled from a Prius, then research to explain what he saw, then write it up, has been hobbit, in the "Brake Fluid" section of his 100,00 mile service post.

-Chap