Brake Fluid Question
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Joined: May 2011
Posts: 60
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From: Wenatchee WA
Brake Fluid Question
On my 85' the color of brake fluid in the front reservoir is a lot darker than the rear reservoir. Is this normal?
I am thinking my master might by bad. I jacked up the rear, put in gear, and really have to push on the pedal to get the rear tires to stop.
No leaks anywhere, but I think the rear reservoir is dropping and the front is gaining. Going to keep an eye on levels.
I am thinking my master might by bad. I jacked up the rear, put in gear, and really have to push on the pedal to get the rear tires to stop.
No leaks anywhere, but I think the rear reservoir is dropping and the front is gaining. Going to keep an eye on levels.
Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 79
From: Monroe OH
NCM Sinkhole Donor
On my 85' the color of brake fluid in the front reservoir is a lot darker than the rear reservoir. Is this normal?
I am thinking my master might by bad. I jacked up the rear, put in gear, and really have to push on the pedal to get the rear tires to stop.
No leaks anywhere, but I think the rear reservoir is dropping and the front is gaining. Going to keep an eye on levels.
I am thinking my master might by bad. I jacked up the rear, put in gear, and really have to push on the pedal to get the rear tires to stop.
No leaks anywhere, but I think the rear reservoir is dropping and the front is gaining. Going to keep an eye on levels.
Safety Car
Joined: Aug 2009
Posts: 3,752
Likes: 276
From: Melbourne, Victoria, Australia
On my 85' the color of brake fluid in the front reservoir is a lot darker than the rear reservoir. Is this normal?
I am thinking my master might by bad. I jacked up the rear, put in gear, and really have to push on the pedal to get the rear tires to stop.
No leaks anywhere, but I think the rear reservoir is dropping and the front is gaining. Going to keep an eye on levels.
I am thinking my master might by bad. I jacked up the rear, put in gear, and really have to push on the pedal to get the rear tires to stop.
No leaks anywhere, but I think the rear reservoir is dropping and the front is gaining. Going to keep an eye on levels.
Brake fluid absorbs moisture and this causes corrosion. You may have seized callipers or the rubber brake hoses have collapsed inside.
Brake pad material makes a huge difference, you really need high metal content for the proper friction. Some standard brake pads have very little friction material, i have been there having to stand on the brake pedal to just try and slow the car.
Hawk pads are really good they require very little brake effort to stop the car, corvette central carries them.
Melting Slicks
Joined: Jul 2005
Posts: 2,649
Likes: 863
Typically brake fluid turns darker as it absorbs moisture, although there are other reasons why it could change color (degrading hydrualic seals etc.). As geradvg says - brake fluid needs to be flushed periodically - most German automakers recommend a flush every three or so years - and it has nothing to do with the German car companies using a different hydraulic system designs.
It's QUITE unlikey that the fluid is moving from one part of the reservoir to another - it is possible, but the master cylinder needs to have seal failure for this to happen. With the engine off - depress the brake pedal a few times to bleed off any power assist. Once the pedal feel "changes" tap the pedal one more time and then press the pedal hard (think 50 - 75 LBS) and hold that pressure for half a minute. Does the pedal drop when you do this ??? If not - the master cylinder probably fine.
Start by flushing the brake system. Use a turkey baster to remove as much fluid from the reservoir as possible, add fresh DOT 3 fluid, and start going through a brake bleed at each of the four wheels (the manual will say to start at the wheel furthest away from the Master cylinder, and there's nothing wrong with that - but you don't really have to worry about that IF the system doesn't have air in it). Keep running fluid through the system (and adding new fluid to the Master Cylinder) till the fluid comes out clear from each caliper. Count on going through at least a quart of fluid - if it's really old - 2 quarts may be required. It's OK to let the fluid in the Master Cylinder reservoir get low - but DO NOT let the reservoir get empty - it takes a LOT of work to get air out of the brake suystem in a car with ABS, unless you have a pressure bleeder, and a factory computer that allows you to activate the valves in the ABS while bleeding. If fluid flows from each of the caliper bleeders - the hydraulic lines are probably fine.
At this point - take the car out for a drive and see if the brakes feel better. I've seen a case where a good fluid flush did wonders for pedal feel.... If they don't feel better - consider putting in new brake pads all around. There are lots of opinions on what pads to use - so I'll let you make that decision - based on how you use the car, your budget and what your timeframe is (get locally - or order via internet). I would recommend lightly sanding the rotor surfaces to allow the new pads to have a roughened up surface to break in against. If after changing the pads - things still don't feel right - you're going to need to do some more troubleshooting. That will involve temporarily defeating the ABS system (pull the ABS fuse) and usig the brakes hard and seeing what wheel doesn't want to lock up. Or - you could choose to rebuild (or get rebuilt) calipers and do it that way.
It's QUITE unlikey that the fluid is moving from one part of the reservoir to another - it is possible, but the master cylinder needs to have seal failure for this to happen. With the engine off - depress the brake pedal a few times to bleed off any power assist. Once the pedal feel "changes" tap the pedal one more time and then press the pedal hard (think 50 - 75 LBS) and hold that pressure for half a minute. Does the pedal drop when you do this ??? If not - the master cylinder probably fine.
Start by flushing the brake system. Use a turkey baster to remove as much fluid from the reservoir as possible, add fresh DOT 3 fluid, and start going through a brake bleed at each of the four wheels (the manual will say to start at the wheel furthest away from the Master cylinder, and there's nothing wrong with that - but you don't really have to worry about that IF the system doesn't have air in it). Keep running fluid through the system (and adding new fluid to the Master Cylinder) till the fluid comes out clear from each caliper. Count on going through at least a quart of fluid - if it's really old - 2 quarts may be required. It's OK to let the fluid in the Master Cylinder reservoir get low - but DO NOT let the reservoir get empty - it takes a LOT of work to get air out of the brake suystem in a car with ABS, unless you have a pressure bleeder, and a factory computer that allows you to activate the valves in the ABS while bleeding. If fluid flows from each of the caliper bleeders - the hydraulic lines are probably fine.
At this point - take the car out for a drive and see if the brakes feel better. I've seen a case where a good fluid flush did wonders for pedal feel.... If they don't feel better - consider putting in new brake pads all around. There are lots of opinions on what pads to use - so I'll let you make that decision - based on how you use the car, your budget and what your timeframe is (get locally - or order via internet). I would recommend lightly sanding the rotor surfaces to allow the new pads to have a roughened up surface to break in against. If after changing the pads - things still don't feel right - you're going to need to do some more troubleshooting. That will involve temporarily defeating the ABS system (pull the ABS fuse) and usig the brakes hard and seeing what wheel doesn't want to lock up. Or - you could choose to rebuild (or get rebuilt) calipers and do it that way.
