Do I Really Need These or Am I Being Scammed Again? - Page 4 - Toyota RAV4 Forums
4.4 Mechanical Intakes, Exhaust, Tune-ups, 4x4 system, Suspension, Brakes, etc.

User Tag List

Reply
 
LinkBack Thread Tools
post #31 of 37 (permalink) Old 01-04-2017, 06:06 PM
Member
Country: BobVila's Flag is: United States
 
BobVila's Avatar
 
Join Date: Apr 2016
Location: Northeast
Posts: 152
Thanks: 10
Thanked 49 Times in 31 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by RAVN4RED View Post
As for water being absorbed, I'm not expert (obvious by my questions, lol) but I've heard it can be absorbed slowly through the brake lines, and perhaps by occasions of extreme heat, boiling down by the calipers.
Water can't be absorbed through the brake lines since it's a closed system. In fact it's closed so well that it can regularly handle 1000-2000 PSI of brake fluid pressure and not leak out.

If brake fluid can't get out at such high pressure, I can guarantee you that nothing at atmospheric pressure can get in.

Moisture can get into the system through the brake fluid reservoir cap, which should be vented. But the vent is tiny. That in theory is where moisture can very very slowly get into the system.

But to get the system to rust from the inside out, you need oxygen. There is no oxygen in the brake system. Where does this myth of brake systems being damaged from moisture in the brake fluid come from? Probably from rust on the caliper pistons when the rubber boot fails. But that has nothing to do with changing your brake fluid.


2017 RAV4 Hybrid Limited
BobVila is offline  
The Following User Says Thank You to BobVila For This Useful Post:
RAVN4RED (01-05-2017)
Sponsored Links
Advertisement
 
post #32 of 37 (permalink) Old 01-04-2017, 09:32 PM
Advanced Member
Country: Dr. Dyno's Flag is: United States
 
Join Date: Jan 2010
Location: Eastern CT
Posts: 6,553
Thanks: 345
Thanked 614 Times in 556 Posts
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by RAVN4RED View Post
Okay, does brake pad replacement count as a repair? I'm guessing not, so what's an example of a repair requiring bleeding. And by bleeding, does that involve replacing all the fluid in the line, or just enough to get air out of the system?
I don't bleed brakes unless I've opened the system for a caliper repair or replacement. Then sometimes I keep filling the reservoir with new fluid but often run a plastic hose from the bleeder back to the reservoir so I don't waste fluid. In any case I only do it on the needed calipers not all of them.
I wonder how many times a full brake fluid replacement service turns into a bigger repair when bleeder screws break.
Dr. Dyno is offline  
The Following User Says Thank You to Dr. Dyno For This Useful Post:
RAVN4RED (01-05-2017)
post #33 of 37 (permalink) Old 01-04-2017, 09:34 PM
Member
Country: RatRAV's Flag is: United States
 
Join Date: Sep 2016
Posts: 124
Thanks: 3
Thanked 18 Times in 16 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by BobVila View Post
Moisture can get into the system through the brake fluid reservoir cap, which should be vented. But the vent is tiny. That in theory is where moisture can very very slowly get into the system.
This is why changing the reservoir fluid is good enough really. In fact, if you go to the dealership and pay for a brake fluid change, this is all they do: suck the fluid out of the reservoir, fill it, done.


Sent from my XT1585 using Tapatalk
RatRAV is offline  
 
post #34 of 37 (permalink) Old 01-04-2017, 10:07 PM
Advanced Member
Country: Dr. Dyno's Flag is: United States
 
Join Date: Jan 2010
Location: Eastern CT
Posts: 6,553
Thanks: 345
Thanked 614 Times in 556 Posts
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by RatRAV View Post
This is why changing the reservoir fluid is good enough really. In fact, if you go to the dealership and pay for a brake fluid change, this is all they do: suck the fluid out of the reservoir, fill it, done.
That must cost about $5. Right?
Dr. Dyno is offline  
post #35 of 37 (permalink) Old 01-05-2017, 08:26 AM
Member
 
Join Date: Nov 2015
Posts: 134
Thanks: 33
Thanked 11 Times in 11 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by RatRAV View Post
This is why changing the reservoir fluid is good enough really. In fact, if you go to the dealership and pay for a brake fluid change, this is all they do: suck the fluid out of the reservoir, fill it, done.


Sent from my XT1585 using Tapatalk
Not really. The moisture that enters through the cap will transfer through the system over time just from working the brake pedal. It takes about 10 minutes to bleed the brakes when you put on pads/rotors. Just do it at that time. No need for any type of special service to bleed the brakes.
joyridin' is offline  
The Following User Says Thank You to joyridin' For This Useful Post:
RAVN4RED (01-05-2017)
post #36 of 37 (permalink) Old 01-05-2017, 11:47 AM
Advanced Member
Country: RAVN4RED's Flag is: United States
 
RAVN4RED's Avatar
 
Join Date: Jul 2013
Location: Idaho
Posts: 825
Thanks: 97
Thanked 102 Times in 96 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
@Dr D and BobVila: Appreciate your takes on this. The reason I asked about motorcycles is because some on the FJR forums have reported getting moisture in their system and losing brakes in aggressive mountain riding as the water boils in brake line. Also notificable when brake fluid changes color, indicates moisture present. Obviously this is comparing apples to bananas, and likely the Toyota RAV brake system is better sealed than a bike.

But I have noticed the color change in the RAV's brake fluid reservoir, I'll stick to my DIY ways and swap it (rare event anyway, once every 7 years). My front pads are about due, so I'll do the full bleed at that time, as per Joyridin' post.

Now the OP is still wondering if the brake service was a scam. Sorry not much help determining that, but probably early. There is a LOT of varied opinions on this, including the difference between Toyota USA and Canada maintenance schedule. So I wouldn't sweat it.

2009 Red RAV4 Base I4 AWD
1989 Chevy Silverado V8 4WD
2004 Yamaha FJR 1300 I4 1WD
RAVN4RED is offline  
post #37 of 37 (permalink) Old 01-05-2017, 01:42 PM
Member
Country: BobVila's Flag is: United States
 
BobVila's Avatar
 
Join Date: Apr 2016
Location: Northeast
Posts: 152
Thanks: 10
Thanked 49 Times in 31 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
RAVN4RED, I change my fluid also because (a) I can DIY it for cheap and (b) I just find car maintenance fun.

Yet at the same time I would not recommend doing it to someone who would pay $150-200+ for it. The odds are it's better to put that money into savings.

Quote:
Originally Posted by RatRAV View Post
In fact, if you go to the dealership and pay for a brake fluid change, this is all they do: suck the fluid out of the reservoir, fill it, done.
I don't know about that. The proper procedure to change the fluid is to use a positive pressure fluid pump and to put the ABS unit into service mode to get the brake fluid moving through it too. At least that's how I've seen it done for other vehicles over the last 20 years.


2017 RAV4 Hybrid Limited
BobVila is offline  
Sponsored Links
Advertisement
 
Reply

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome