2013 Auris Hybrid - brake fluid bleeding (not Using the Techstream)

[Fostel]

I am going to replace the brake fluid on my 3rd gen.
The front pads are getting thinner and will be replaced too.

1.     Should I bleed the brakes when the fluid level is low (old thin pads)?
2.     or it would be better to change the pads first and then flush the fluid?

I would think that the 1st option is better avoiding any oil getting to the new pads but I am wondering if there is any right way to do it.

Thanks.

[TonyHSD]

Hi, 

Are you aware hybrids has special procedures for changing brake fluid and working on brakes in general as they have electronic brake booster? There are some helpful videos on YouTube you can watch to familiarise yourself  before proceed just to be on the safe side. For brake fluid change , first replace you brake pads and discs as the new one will pushback old fluid higher into be reservoir, then with car off and system depressurised take out all old fluid from the tank with syringe, add new one to the max and do your flush through the bleeding nipples. Keep watching fluid level often and top up full as necessary. For rear brakes flush do kit hold brake pedal pushed longer than 3 sec each time while bleeding screw is open as the pump will drain the tank quickly and you may introduce air into the system. 
Here some video. 
https://youtu.be/UZ1wpW62L7U

[AisinW]

You should not use the electronic brake booster in hybrid, it may drain the 12V Battery too much. 

Just use regular vacuum from the bleeder and stop till you satisfy. The brake fluid has negligible wear even after 100k miles. Don't waste your time on brake fluid change in hybrid. It is just our ego and obsolete maintenance schedule. 

 

The pads normally wear about 1/2 at around 70k miles. It lasts at least 150k miles for most of us. Change the pads first, brake bleeding is not necessary unless you touch the banjo bolts or bleeder screws. We never need to bleed the brakes when changing pads or rotors. 

[AisinW]

I just test my brake fluid today. 5 years no flush and the color is practically identical with a new fluid.  Water contents is below 1%.  I am convinced that brake fluid change in hybrid every 2 years is overkill.  

[TonyHSD]

8 minutes ago, AisinW said:

I just test my brake fluid today. 5 years no flush and the color is practically identical with a new fluid.  Water contents is below 1%.  I am convinced that brake fluid change in hybrid every 2 years is overkill.  

Indeed, plus the dealers all they do is suck some fluid from the tank with syringe and add new one if they do anything at all. 4-5 years perhaps a good time for replacement. 

[AisinW]

I think it is relevant only at the first 3 years when we still have bumper to bumper warranty and we can do it outside dealership. After 3 years, I chose to do all maintenance by myself because hybrid system still have 5 years warranty regardless who do the maintenance (no need to be mechanics with VAT number). 

After 5 years, I think I will not to worry about coming to the dealership anymore. The hybrid-system-check and relax-warranty can be activated anytime anyway whenever we need to sell the car. 

I agree with Tony that around 5 years is sufficient. I am planning to use DOT5.1 because Toyota even sell it for almost the same as DOT3.  What I know, DOT5.1 is more resistance to water contamination and more stable. 

[Davidhee58]

Regarding brake fluid breeding, I got 2 questions to ask those DIY experts.

1. Has anyone tried vaccum pump method to bleed the brake fluid? from the car_care_nut video, it looks not easy to suck the fluid out. 
2. which brake fluid do dealerships use for car service? Dot3 or Dot 4? at the toyota online store, seems they only sell Dot 4 fluid, I couldn't find any Toyota Dot 3, can Dot 3 be mixed with Dot4? as I don't know which brake fluid was added by the toyota technisian at the last service.

[TonyHSD]

1 hour ago, Davidhee58 said:

Regarding brake fluid breeding, I got 2 questions to ask those DIY experts.

1. Has anyone tried vaccum pump method to bleed the brake fluid? from the car_care_nut video, it looks not easy to suck the fluid out. 
2. which brake fluid do dealerships use for car service? Dot3 or Dot 4? at the toyota online store, seems they only sell Dot 4 fluid, I couldn't find any Toyota Dot 3, can Dot 3 be mixed with Dot4? as I don't know which brake fluid was added by the toyota technisian at the last service.

Hi David, 

I had done the brakes of my two Auris myself a couple of times and always used ATE Dot3 brake fluid bought from Eurocarparts https://www.eurocarparts.com/p/ate-dot3-brake-fluid-1ltr-524770202

I never done any vacuum, pump or anything method so can’t comment on that. I follow the instructions from a us diy guy on YouTube and some common sense. Never had any trouble with the process or problems afterwards. 
You can mix dot 3 and dot4 without any problems, they are made compatible. I prefer to stay with dot3 although been mixing previously with dot4. Now the system is flushed and only dot3 ate inside. 
1ltr is enough to do it yourself through the bleeding nipples on each calliper, but you can buy two bottles just in case. 
When doing the rears note that when pressed the brake pedal the electric pump will pump out a lots of fluid so be quick opening and closing the nipple. Also if I remember correctly the pump should not be used continuously over long time. 

You can depressurise the system, then disconnect negative terminal on the 12v Battery. Do the old school front callipers. Re connect the negative terminal, wait the system to pressurise itself, check fluid level all the time and between each tasks, set the car into valet mode , flesh the rear callipers and after you are done, let the car seats on its wheels at level place, turn off ignition and wait the system to depressurise itself, check brake fluid level should be at max top line. Job done ✅ 

[Davidhee58]

2 hours ago, TonyHSD said:

Hi David, 

I had done the brakes of my two Auris myself a couple of times and always used ATE Dot3 brake fluid bought from Eurocarparts https://www.eurocarparts.com/p/ate-dot3-brake-fluid-1ltr-524770202

I never done any vacuum, pump or anything method so can’t comment on that. I follow the instructions from a us diy guy on YouTube and some common sense. Never had any trouble with the process or problems afterwards. 
You can mix dot 3 and dot4 without any problems, they are made compatible. I prefer to stay with dot3 although been mixing previously with dot4. Now the system is flushed and only dot3 ate inside. 
1ltr is enough to do it yourself through the bleeding nipples on each calliper, but you can buy two bottles just in case. 
When doing the rears note that when pressed the brake pedal the electric pump will pump out a lots of fluid so be quick opening and closing the nipple. Also if I remember correctly the pump should not be used continuously over long time. 

You can depressurise the system, then disconnect negative terminal on the 12v battery. Do the old school front callipers. Re connect the negative terminal, wait the system to pressurise itself, check fluid level all the time and between each tasks, set the car into valet mode , flesh the rear callipers and after you are done, let the car seats on its wheels at level place, turn off ignition and wait the system to depressurise itself, check brake fluid level should be at max top line. Job done ✅ 

Thank you Tony for your very detailed information👍

[TonyHSD]

16 minutes ago, Davidhee58 said:

Thank you Tony for your very detailed information👍

You are welcome. 

[Saxmaniac]

I saw the car care nut video, I will be doing mine this summer. I got a reply from him when I asked if it's ok to use a pressure bleeder instead of vacuum pump and he said yes it's fine. Vacuum pump can work but you get air sucked in round the threads of the bleed nipple. It's not a major problem but looks like air is coming from system when it's actually not 

[Davidhee58]

On 1/10/2023 at 10:23 AM, AisinW said:

What I know, DOT5.1 is more resistance to water contamination and more stable.

Hi John, what I leant is DOT 5.1 is more hygroscopic than DOT 4 and therefore absorbs more moisture, it will need to be changed more often. 

[AisinW]

6 hours ago, Davidhee58 said:

Hi John, what I leant is DOT 5.1 is more hygroscopic than DOT 4 and therefore absorbs more moisture, it will need to be changed more often. 

It is about the same in terms of hygroscopicity. It is more about the wet boiling temp and price.  Only DOT4 has lower boiling temp than DOT3 although DOT4 dry boiling temp is higher. 

DOT5.1 is just too expensive years ago but not today. 

[Davidhee58]

I just checked the last service invoice of my car at the dealer, they used Dot.5.1 (T 08823-80005), frome the price (£9.32), I guess it was 0.5L, this meant they only sucked out the old fluid  from the reservoir and added ~500ml back, unbelievable, I never thought  this was the brake fluid change the dealership did for the full service. To bleed the brake system properly, at least 1L fresh brake fluid is needed, am I correct?

I haven't done brake fluid change before. I am planning to do it later, the Toyota user manual recommends Dot 3 or Dot 4, but it seems Totoya has stopped selling Dot 3 for unkown reasons, I don't know if I should use Dot 4 or carry on to use Dot 5.1. 

[Eddiefh]

Same as mine just checked my in voice slightly different part number but same volume . 
after they used wrong oil and now this will either try another dealer or diy , and relax is a joke as well 

[Davidhee58]

1 hour ago, Eddiefh said:

Same as mine just checked my in voice slightly different part number but same volume . 
after they used wrong oil and now this will either try another dealer or diy , and relax is a joke as well 

I don't undersatnd why people believes the dealer service history is so "valuaeble"😀

[Eddiefh]

On 1/21/2023 at 3:28 PM, Davidhee58 said:

I don't undersatnd why people believes the dealer service history is so "valuaeble"😀

I was drawn in by relax warranty 

[AisinW]

On 1/21/2023 at 2:39 PM, Davidhee58 said:

I just checked the last service invoice of my car at the dealer, they used Dot.5.1 (T 08823-80005), frome the price (£9.32), I guess it was 0.5L, this meant they only sucked out the old fluid  from the reservoir and added ~500ml back, unbelievable, I never thought  this was the brake fluid change the dealership did for the full service. To bleed the brake system properly, at least 1L fresh brake fluid is needed, am I correct?

I haven't done brake fluid change before. I am planning to do it later, the Toyota user manual recommends Dot 3 or Dot 4, but it seems Totoya has stopped selling Dot 3 for unkown reasons, I don't know if I should use Dot 4 or carry on to use Dot 5.1. 

DOT 5.1 is superior in almost all aspect to DOT3 and DOT4.  Some Toyota dealers use it as the standard since couple years ago because of that reason.  DOT4 has lower WET boiling temp than DOT3.  Meanwhile DOT5.1 are always higher in dry or wet boiling temp.  Just get €5 brake fluid tester from LIDL and check it every other year.  You will see how much water content introduced to the system.  You will be surprised how good the seals in Toyota.  I never have brake fluid with water content higher than 1% in any Toyota with less than 5 years brake fluid change. I changed it in some of non hybrid in 5-6 years just because it gets darker over time, not because of water contaminations.  My 2002 Nissan Altima brake fluid failed strip test (copper content) after roughly 6 years meanwhile my HSD  never have this issues after 6 years. I changed it just because I want it.  To bleed the system it does not have to be 1L. Usually, shop stop the bleeding once the fluid is already clear.  It is really hard to distinguish the new and old fluid in hybrid cars even after 5 years. 

[Stivino]

If your car takes DOT4, you can't use DOT5.1.

[AisinW]

27 minutes ago, Stivino said:

If your car takes DOT4, you can't use DOT5. 

Yes you can always use DOT 5.1 in any DOT4 or DOT 3. DOT 5 silicon and DOT 5.1 glycol are completely different. DOT4 is more sensitive to water contamination than DOT3 or DOT5.1 .  I attach the brake fluid after 5 years from the reservoir. I took it as sample because it is not easy to take the picture and show how clear and bright it is in the reservoir.  But my point is, don't overdo  brake fluid change in Hybrid cars. Every 5 years is more than enough regardless DOT3,4, or 5.1.  Spent your money better on more frequent Oil change instead.  Every 7-8k miles/ 8 months is better if our car have tendency to consume engine oil.  

[Stivino]

You are correct, I omitted the 1. Now corrected.

[Eddiefh]

But can they be mixed as I think going of the invoice the dealer has sucked out of reservoir has apposed to bleeding full system 

[AisinW]

3 minutes ago, Eddiefh said:

But can they be mixed as I think going of the invoice the dealer has sucked out of reservoir has apposed to bleeding full system 

Don't worry. They are mixed without any problem at all.  In facts, our car only need DOT3 (lowest grade). So, putting better fluid like DOT 5.1 only increase the life of the braking system.   We should not put DOT 3  in a car with DOT 5.1 standard from factory, it may reduce the braking performance.   It is like putting full synthetic oil on 1995 Corolla that use standard 5W-30 non synthetic oil.   Or putting longlife 0w-20 oil in Auris, there is no ill effect besides better lifespan on the oil.   

[Davidhee58]

Hi John,  if the brake fluid level in the reservoir is close to the max,  roughly, how much fluid is there? I had a quick look at my car, it seems to me quite a lot, ~400ml?  you said to bleed the system it does not have to be 1L, can it be possibly done in 0.5L by Toyota technisian? if so, I don't need to flush the brake system as my car had a full service including the brake fluid change at the dealership 3 years ago, if they only replaced the fluid in the reservoir, this means my car brake fluid has not been flushed for 6 years. Yes, the fluid in the reservoir looks clear and the water content is <1% so far,  this may only tell me the fluid in the reservoir is ok, but the fluid in other parts of the system may be not in same conditions as they weren't flushed before. Or maybe I am wrong, over the time (3years), the fresh fluid in the reservoir has been mixed well with the old fluid in the far ends of the system already, that seems difficult to me, particularly for hybrid car as it uses engine brake in most of time.          

[AisinW]

I think it is supposed to be 0.5-1L depends on how much you want to bleed the old fluid. I believe the reservoir holds about 300mL.  I  tried/tested the fluid from the bottom before, the water content and color were identical. It makes sense because they are all connected and chemical potential will keep the whole brake fluid system in the same mixture via diffusion.  The brake fluid gets dark in normal cars after about 4-5 years but not in hybrid. I was in USA for decades and we do not change brake fluid unless we change calipers, brake booster, or other parts on the brake system.  In North America, we do not have that requirement to keep Toyota warranty. It is only recommended service and sometimes dealership do strip test if necessary to check the additives content in the brake fluid after 3 years.  The heat generated from the brake cause degradation and depletion of antioxidant in brake fluid. The strip test detect how much copper diluted in the brake fluid that tell us how much the wear on the additives.

From my experience, the brake lines corrosion always caused by external damage (stone or salt).   Fortunately, the brake system on post Prius 2004 are very well coated and rarely we have corrosion issues like in 1990s cars.   

In UK and Europe in general, we have tradition for changing brake fluid every 2 years, and spark plugs 3-5 years.  Toyota exploit it by putting them in the maintenance schedule although the Denso Iridium is rated (120k miles/10 years) and brake fluid is changed if necessary depends on wear and contaminations, not by schedule. If you do not care about Relax-Warranty, you do not have to change the brake fluid every 2 years.