Brake fluid change, just the farthest or all 4 calipers?


  #1  
Old 07-05-24, 11:51 AM
M
Member
Thread Starter
Join Date: Sep 2003
Location: Arlington, VA
Posts: 1,060
Received 4 Upvotes on 4 Posts
Brake fluid change, just the farthest or all 4 calipers?

For the longest time I've just gone to the right rear caliper and tightened the bleeder screw back up once the old fluid is out and new fluid is coming through. There will be a small amount of old fluid in the other calipers but I figured that doesn't matter much if I'm changing the fluid regularly, any other opinions?
 
  #2  
Old 07-05-24, 12:09 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,972
Received 4,149 Upvotes on 3,726 Posts
Brake fluid is hydroscopic.
It holds moisture which causes internal tubing rusting.
I would flush the entire system.
 
  #3  
Old 07-05-24, 01:32 PM
S
Group Moderator
Join Date: Oct 2004
Location: WI/MN
Posts: 19,214
Received 1,288 Upvotes on 1,226 Posts
New brake fluid is contaminated by the old stuff. Replace it all.
 
  #4  
Old 07-05-24, 03:34 PM
M
Member
Thread Starter
Join Date: Sep 2003
Location: Arlington, VA
Posts: 1,060
Received 4 Upvotes on 4 Posts
I typically change the fluid whenever it turns from yellow to light brown.Should it be done sooner (or based on mileage)?
 
  #5  
Old 07-05-24, 04:03 PM
C
Member
Join Date: May 2015
Location: USA
Posts: 3,209
Received 182 Upvotes on 149 Posts
Subaru specifies brake fluid changes every 30k miles and they have the bleeding order in the service info. Following the recommended order minimizes cross contamination and waste of new fluid. Perhaps your vehicles service info includes a recommended interval and order. Most important is to use the correct fluid DOT3, DOT4, or DOT5.
 
  #6  
Old 07-05-24, 04:23 PM
A
Member
Join Date: Aug 2015
Location: USA
Posts: 1,131
Upvotes: 0
Received 127 Upvotes on 110 Posts
many probably never change it, or it gets changed with a bad component, caliper, hose, rusted out line, master cylinder, etc.
 
  #7  
Old 07-06-24, 06:57 AM
ukrbyk's Avatar
Member
Join Date: Mar 2010
Location: USA/ Pacific NW
Posts: 3,683
Received 63 Upvotes on 54 Posts
You most likely have split fail safe brake system. That means, you have TWO independent lines coming out of master. They normally are criss crossed and doing one calliper does nothing to the other line components. Basically, you are driving with new fluid in the rear calliper, contaminated fluid in the front calliper on the same line and old fluid in the opposite line both callipers.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: