Long Life Brake Fluid?

#1
I use my Corolla D-4D less than 4,000 miles per year.
Never in some years.
I don't have facilities to jack up all four wheels.
Garages are expensive and can be unreliable.
Is changing brake fluid every 2 years necessary?
Motul DOT 5.1 Brake Fluid claims to be "Long Life" but do not specify how long!
Your views, comments and brake fluid recommendations will be appreciated.
 
#2
Brake fluid is hydroscopic, which means it retains moisture. As long as the moisture content is acceptable there is no need to change. From what I can tell less than 2% moisture content is fine. If the moisture level gets too high then it rusts the inside of the break lines and cylinder and reduces breaking power, which is not what you want. You don't necessarily need to change the fluid every two years, it depends on the moisture content.
 
#3
I am 76 years old and have had a lot of cars in my lifetime and have had some high mileage cars. I have not ever changed break fluid in any of them and never had any problems with any of them.
 
#6
About 500 miles after the last fluid change, the Corolla was garaged for over six years.
Checked the fluid in the reservoir today. It is still golden in colour.
So is it okay?
 
#8
Corolla use DOT 3. I know you can use DOT 4 with no issues, not sure about going up to DOT 5. Sorta like fuel you can use premium if you want but not necessary, however if you car calls for premium fuel you can go down. Same with brake fluid if the manual calls for DOT 4 you can't use DOT 3.
 

JobCF

New Member
#9
JobCF you need to check moisture content not colour. There are tools you can get to check the moisture. I got one off eBay.
Good suggestion, thanks!
Saw some YouTube videos. Apparently does the job.
So many of these at eBay from as low as £2.19 from China. They all look alike!
I wanted fast delivery so bought from a UK supplier for £3.69
 
#10
Corolla use DOT 3. I know you can use DOT 4 with no issues, not sure about going up to DOT 5. Sorta like fuel you can use premium if you want but not necessary, however if you car calls for premium fuel you can go down. Same with brake fluid if the manual calls for DOT 4 you can't use DOT 3.
Corolla User Manual specify DOT 4 for brakes and clutch.
Taken from Motul Technical Data Sheet for Motul Brake fluid, DOT 5.1:
Dry boiling point 270°C. Wet boiling point 185°C
The Wet boiling point is representative of the fluid after one year of use.
The high Wet boiling point (185°C) is superior to DOT 4 (155°C mini) and DOT 3 (140°C mini) fluids enable to use of this product longer.
 
#13
Thank you all for your comments.
The car is a 2004 Corolla 2.0 D-4D T Spirit [116ps]
Brake Fluid Flush and DOT 4 fluid at 50,439 miles on 7 Dec 2011
Mileage now 51,150. (The car was off the road and garaged for over 6 years.)
Brakes work okay without and sponginess.
Waiting for delivery of a Brake Fluid Tester that indicates water content.
Will report back.
 
#14
I tested the Brake Fluid Tester Pen in three ways:
1. New fluid. Green LED. < 1%
2. In the 7+ year old fluid in the car. Reading < 2%
(Last changed on 7 Dec 2011. The car was out of use and garaged for over 6 years.)
3. A small quantity of new fluid with few drops of water. Reading > 4%
So I can postpone changing the fluid till the reading show < 3%

Many at eBay and Amazon. All look the same but with a huge difference in price.
For fast delivery, I bought from a UK seller for £3.69.
 
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#17
As I know, a standard brake fluid has a recommended change interval of two years. As a brake fluid, Motul is a trusted name and it also recommends to change it every two years. But currently, I am using Bosch ESI6-32N. I haven't change it yet, but it's recommended change interval is up to 3 years.
 
#18
I tested the Brake Fluid Tester Pen in three ways:
1. New fluid. Green LED. < 1%
2. In the 7+ year old fluid in the car. Reading < 2%
(Last changed on 7 Dec 2011. The car was out of use and garaged for over 6 years.)
3. A small quantity of new fluid with few drops of water. Reading > 4%
So I can postpone changing the fluid till the reading show < 3%

Many at eBay and Amazon. All look the same but with a huge difference in price.
For fast delivery, I bought from a UK seller for £3.69.
Since the post above, the Corolla did about 1,500 miles
I tested the fluid again a couple of weeks ago.
Still well below 3%
 
#19
Corolla use DOT 3. I know you can use DOT 4 with no issues, not sure about going up to DOT 5. Sorta like fuel you can use premium if you want but not necessary, however if you car calls for premium fuel you can go down. Same with brake fluid if the manual calls for DOT 4 you can't use DOT 3.
I just notice an error in my response and would like to clarify, what I meant to say was if you car calls for premium fuel you CAN NOT go down to regular or you risk damage.
 
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