I've spent most of today working on my '95 LT1. I drove it this morning and noticed a low "scruff-like sound" when I used the brakes. Well, I had all the supplies to rebuild the brake system delivered last week (thank you, Corvette Central) except brake fluid. A quick stop by Checkers and purchasing two large bottles of synthetic brake fluid on the way home and I was ready.

The old pads were pretty well used up, the rotors looked better than I though they would; a quick trip to the brake lathe to get the old dust off and get rid of the glazed areas and the rotors were good as new (I'm glad I didn't have to buy new rotors - money is getting tight). I checked the run-out, that was within specs for all four rotors. A hour and a can of WD-40 was devoted to the emergency brake cables - links were tighten; grease and oil were placed to the appropriate areas.

My pressure-bleeder had a broken neck to the part that fit on the master cylinder so the Mighty Vac was used to bleed the lines. I was replacing the brake lines with braided lines from the car to the brake cylinders but didn't want brake fluid on my garage floor.

I was shocked to see what I removed from the brake lines/master cylinder:





No, it's not used motor oil or really strong coffee - it's ancient brake fluid - the very worst I've ever seen.

Needless to say, my brake system now has clean Valvoline Synthetic brake fluid.

My '79 Vette has squealing brakes and I'm planning to replace the pads within the next month. I really fear what its brake fluid looks like.

 

Two more views at higher resolution:







So gang, a quick question: Can 15 years of neglect cause the fluid to become this dirty (and a lot thicker than the new brake fluid)? I know brake fluid is hydrophillic and loves to absorb moisture when it can, so can that be a contributing reason for the old fluid to be dark? Have the brakes been severely overheated to cause this?

Any information will be greatly appreciated.

 

I know, makes a guy wonder how the brakes even worked with that
sewage water.

When I got my vette in 1997, my fluid looked just like that, and my brakes seemed to work ok, although the pads and such needed upgraded, it was a functioning system.

I flushed it all out, and cleaned the resovoirs, they were black too,
and its been clear as ice ever since, feels good every time I look at it, not to mention use them, ha.

 

Yeah, it's due.

 

I just did the braided brake lines and flushed the brake fluid this afternoon. There was a layer of sediment in the reservoirs and the fluid was dark like the OP's. I don't think it's ever been flushed out before, so...26 yrs of filth built up in there

 

Look around and see all the pretty engine compartments, chrome, polish, metalflake paint......... Comments and concerns about what motor oil to use, burn premium gas cause its what "my baby" likes.

And the bone heads have chunky BLACK brake fluid!!!!

Makes me crazy

 

Can the brakes be damaged or oeverheated ?

If you feel up to it, take off one of the front calipers, and take it apart,
remove the boot, and look at the cylinder and all.
Maybe those need rebuilt too, or cleaned at least.
An easy job really. I did all 4 of mine, after I saw my fluid was black sludge. My pistons cleaned up nice, and with a boot, rings,
all in the rebuild kit, its all fresh again.

Just be sure if you cant get the piston out, and use an air hose
point that thing away from your body, ha, it could shoot out like a shotgun slug, no lie.

 

Yeah, I think it is recommended to change the brake fluid every year or two. Another problem of not changing the fluid regularly, is you can get rust in the brake system. I think this would be at the calipers.

 

 

I looked at the owner's manual for this car and guess what? There is no info on changing brake fluid, only for checking the fluid level in the MC.

I'll stop by Checkers or Advanced Auto later today to get another two bottles of brake fluid and will be prepared for what to expect from the '79.

 

94 to 97 like that kinda of brake fluid
Usually the abs and asr go crazy and pulsate the brakes when you step on them ,when the fluid gets like that every 2 years.I just suck it out and put in new just did that last week,another chevy defect ,like the chevette and vega.OH! forgot about the controled seapage the engine always has.

 

I highly doubt you will find info (or even a change interval) on changing the brake fluid in the owners manual of any car.

 

Just did my brakes and clutch fluid replacement and bleed this weekend. I wish I took a picture so we could have a contest who's was more disgusting.
I feel the same way when I see that pretty clean fluid in the reservoirs - Schwing !

 

Thats not bad I had an 88 where the old brake fluid was really thick. Looked like chocolate pudding and had almost the same consistency.

Now for the bad news, well it was my experience - remeber I spend time on the road course with mine.
I flushed mine with ATE blue when I bought it. After every event I had to bleed, and flushed every other event. Switched to ATE gold after a year, same thing, Last year I switched to less expensive and more available Valvoline synpower, same bleed flush schedule.

I was ALWAYS getting grey fluid out! So this winter I replaced the master, booster and all 4 calipers. NO MORE always grey fluid. Before I had to pump 6 - 8 times to get clear fluid at a wheel. Now it is 1-2 which is perfect! Only had 2 events, but so far I'm very happy.

 

I try to change my brake fluid, powertsteering fluid and hydraulic clutch fluid every 2 years or so. Even after only two years these fluids are starting to get a little discoloration and this is with no track time just street driving .

 

newer cars say flush every 2 yrs.
brake fluid will attract up to 5% water every year from what I've read.
Some people say it can gain water through plastic bottles and they only use fluid out of a sealed metal can.
My neighbor never did anything to her 95 Olds 98. Last week they put a new master cylinder on it. The trash and water mixed with the fluid and corroded the bottom of the bore and ate up the seals.
The big deal people forget about is the ABS. It has some tight tolerance solenoids. When trash hangs them up it's big buck to fix.

JS

 

Anytime I opened a bottle of new brake fluid, its always been clear.

 

With fluid that dirty what kind of symptoms did you experience? Did the new fluid give you a night and day different feel?

I haven't changed mine for about 2 years, I'm wondering if I'm due.

 

Yep, every 2 years on the street stuff.

2 times a year on the racecars, bleed the calipers every race, fluid in the caipers gets a very light gold color in one race.

 

After a couple races mine is black as night. I do mine 2-3 times a year or after so many events.