GLK 350 losing brake fluid
11-23-2018, 05:00 AM
#1
Newbie
Thread Starter
GLK 350 losing brake fluid
My 2010 GLK 350 has recently started losing brake fluid. I have checked all of the lines and calipers and found no indications of any leaks. My first thought was master cylinder, but there is no sign of fluid leaking at the rear of the cylinder where it mounts to the booster as is the normal indicator. Does anyone have any further insight??
BTW, the pedal has finally started to get spongy, just like it would be a master cylinder failure.... But where is the fluid going???
BTW, the pedal has finally started to get spongy, just like it would be a master cylinder failure.... But where is the fluid going???
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richsmoke (11-23-2018)
11-23-2018, 09:16 AM
#3
MBWorld Fanatic!
It sounds like a major pain just to get the dye circulated through the Brake system, then you probably need to flush it out. Did you check the antilock module for oil residue. I’m just guessing here on what to do.
11-23-2018, 11:23 AM
#4
Newbie
Thread Starter
11-23-2018, 11:51 AM
#5
Senior Member
Why do you think it is losing fluid? How often do you have to fill the reservoir?
As the pads wear the pistons in the calipers move outward and stay there so more brake fluid stays in the calipers instead of the reservoir. So as the pads wear the level goes down. If the level goes down fast and you have to keep refilling then you have a leak. If it's slow and consistent then it is normal.
If you do have a leak and a spongy pedal it could be leaking out the back of the master cylinder into the vacuum booster. At some point I would expect a visual indication of fluid.
As the pads wear the pistons in the calipers move outward and stay there so more brake fluid stays in the calipers instead of the reservoir. So as the pads wear the level goes down. If the level goes down fast and you have to keep refilling then you have a leak. If it's slow and consistent then it is normal.
If you do have a leak and a spongy pedal it could be leaking out the back of the master cylinder into the vacuum booster. At some point I would expect a visual indication of fluid.
