911 Brake Fluid Flush - How often?
12-02-2020, 07:03 PM
#16
Rennlist Member
Checked Lexus ES and RX - 3 years for brake flush, spark plugs 60k miles or 72 months.
Mercedes brake flush same as Porsche but Mercedes is very aggressive with their differential fluid replacement. 2000k miles for first one if you have an AMG model
Mercedes brake flush same as Porsche but Mercedes is very aggressive with their differential fluid replacement. 2000k miles for first one if you have an AMG model
12-04-2020, 02:47 AM
#17
12-04-2020, 03:04 AM
#18
I don't think any of this kind of stuff is listed in the Owner's Manual. These things are listed in a separate thinner booklet dedicated to Maintenance Schedules and a place for the dealerships to put their service stamps. Maybe yours is missing? If it is, they are easy to pick-up on eBay.
“Additional work” written 90˚ on L side of page! It DOES state change brake fluid every 2 years.
IDK WHY Porsche did not list it in the section with work to be performed every 2 years or 20K miles, 40k, 60k, etc.
12-04-2020, 03:13 AM
#19
Any thoughts on:
I have seen nothing re problems with brake fluid other than moisture content, which of course is an issue & the main reason to change it.
I have also heard that since brake fluid does not circulate, measuring water % at the brake fluid reservoir does not give you a true test of the moisture content at the calipers & elsewhere in the system.
I have seen nothing re problems with brake fluid other than moisture content, which of course is an issue & the main reason to change it.
I have also heard that since brake fluid does not circulate, measuring water % at the brake fluid reservoir does not give you a true test of the moisture content at the calipers & elsewhere in the system.
12-04-2020, 06:23 AM
#20
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12-04-2020, 09:19 AM
#21
Drifting
This ^^^^ is only partially accurate. Brake fluid is hydroscopic (naturally attracts moisture). Overtime its H2O content as a percentage of fluid will increase due to ambient humidity. The brake fluid system is not air tight. The higher H2O saturation, the lower the boiling point of the fluid. If the fluid should boil as a result of heating the fluid through braking, the fluid becomes gaseous. The boiling process will create the gases and brakes will be compromised.
If one engages in regular spirit driving, track driving or similar driving it is advisable to change fluid every year. For example, I have taken readings of my fluid and ranged >1% but <2% H2O and found my brakes compromised (mushy) during heavy continuous braking. Brake fluid testers are good for information, but it all depends on the heat the system generates and the amount of H20 saturation.
If one engages in regular spirit driving, track driving or similar driving it is advisable to change fluid every year. For example, I have taken readings of my fluid and ranged >1% but <2% H2O and found my brakes compromised (mushy) during heavy continuous braking. Brake fluid testers are good for information, but it all depends on the heat the system generates and the amount of H20 saturation.
12-04-2020, 09:28 AM
#22
Rennlist Member
Correct, this is the reason that bleeding brakes between flushes is SOP with track duty.
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