Brake Fluid change
Thread Starter
Burning Brakes
Joined: Feb 2007
Posts: 1,149
Likes: 5
From: Grafton WI
Brake Fluid change
How often should the brake fluid be flushed and changed. I have a '98 that is still original and I am trying to determine the best maintenance items for this year. The car has 50000 miles. Fuel filter was changed last year. Any suggestions?
Burning Brakes
Joined: Jul 2004
Posts: 932
Likes: 0
From: Las Cruces New Mexico
I try to change all fluids at 50k and 100k. I am now at 105k and need to do it again. I personnelly would change the brake fluid if it is still the original fluid but don't have a mechanical or scientific reason why.
Le Mans Master
Joined: Aug 2004
Posts: 7,765
Likes: 1
From: Kansas City MO
I was going to ask why, but you answered, I cannot think of any reason to, or easy way of changing it.
Le Mans Master
Joined: Feb 2006
Posts: 6,513
Likes: 0
From: Dallas Texas
St. Jude Donor '11
I changed mine when I changed my brake pads. All I did was have someone pump the brakes until clean/new fluid came out of the bleed screw (did that for all 4 calipers). You just have to make sure that you keep the level of fluid in the booster steady so you don't get air in the lines.
Le Mans Master
Joined: Aug 2004
Posts: 7,765
Likes: 1
From: Kansas City MO
I changed mine when I changed my brake pads. All I did was have someone pump the brakes until clean/new fluid came out of the bleed screw (did that for all 4 calipers). You just have to make sure that you keep the level of fluid in the booster steady so you don't get air in the lines.
Also, what was your reason for changing it?
Le Mans Master
Joined: Feb 2006
Posts: 6,513
Likes: 0
From: Dallas Texas
St. Jude Donor '11
I did it for piece of mind mostly. Plus, I was having to bleed the brakes anyway due to the new pad installation, so I just tokk it a little beyond getting the air out. All it added was a few extra bucks for the big bottle of brake fluid as opposed to the little one. So I figured it couldn't hurt.
Safety Car
Joined: Oct 2000
Posts: 4,949
Likes: 10
From: Monticello MN
Basically, I just looked for a color change in the fluid to know when the old was out and the new was in. I didn't do anything scientific and there is probably a mix of some old with the new.
I did it for piece of mind mostly. Plus, I was having to bleed the brakes anyway due to the new pad installation, so I just tokk it a little beyond getting the air out. All it added was a few extra bucks for the big bottle of brake fluid as opposed to the little one. So I figured it couldn't hurt.
I did it for piece of mind mostly. Plus, I was having to bleed the brakes anyway due to the new pad installation, so I just tokk it a little beyond getting the air out. All it added was a few extra bucks for the big bottle of brake fluid as opposed to the little one. So I figured it couldn't hurt.
Ed
Melting Slicks
Joined: Oct 2006
Posts: 3,447
Likes: 6
From: Los Angeles
There's also the ghetto method. Take a turkey baster and remove most of the old fluid out of the resovoir. (remove only to the low mark, or just before the end of the resovoir, any further may get air in) Then top it off with new fluid. Drive it for a day or so. Repeat the process the next day. Each day the resovoir will be less and less "dirty" from the old fluid. Takes about 3-5 times. Sure it's not as effective as a full bleed, but it will replace most of the fluid... which is better than having all old/dirty fluid. It's easy to do also. Recommend you buy a baster for this job exclusively, or your next thanksgiving turkey may taste like brake fluid. 
Its an option if you don't have the time to bleed it out completely right away.
Its an option if you don't have the time to bleed it out completely right away.
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Pro
Joined: Jan 2000
Posts: 741
Likes: 47
From: Indianapolis IN
I will probably change fluid when I get new pads and rotors this Spring, however, I've never changed it on any other car I've owned, and never had a problem. So, I was wondering what the mechanism is that supposedly wears it out. What makes the color get darker and does that affect hydraulic performance? Anyone know?
Ed
Ed
I believe that the coloring is coming from that moisture, as well as coming off of the various seals in the brake system as they age.
Melting Slicks
Joined: Feb 2007
Posts: 2,787
Likes: 139
From: center of Kalifornia
Brake fluid does absorb moisture with age and then this lowers the boiling point. If and when it gets that hot, air forms and air is compressible, thus no brakes. A few years ago I had a ten year old motorhome and the original fluid. I boiled the brakes going down a series of hills in Nevada, E ticket ride, barely stopped her. Changed the fluid, it was very dark, good as new now. I suck out the reservoir first, then fill with clean and bleed out the rest. There is other pressure methods but this you can do in the garage.
Safety Car
Joined: Dec 2003
Posts: 3,743
Likes: 1
From: Keep Me Working...Buy A Ford!
Haven't done it yet, but have new stainless lines from L.A.P.D., 4 Speed Bleeders for the calipers, and three pints of Motorcraft DOT 3 high performance brake fluid. They say Motorcraft fluid is one of the best you can buy.
Melting Slicks
Joined: Aug 2005
Posts: 2,995
Likes: 61
From: Fort Wayne IN
I'd suggest every 24 months regardless of the miles driven. Dot 3/4 will pick up moisture over time and cause corrosion in the ABS system. Damage it and it'll be expensive. IMHO it's cheap insurance. $.02
Thread Starter
Burning Brakes
Joined: Feb 2007
Posts: 1,149
Likes: 5
From: Grafton WI
Thanks to all for the advice. The mechanic at the local Corvette garage said pretty much the same things. He said that every time the temp changes drastically, it adds some moisture to the system. I live in Wisconsin, so that happens often. I will have it done next week. He said I will notice the difference. Thanks again!!
Safety Car
Joined: Mar 2006
Posts: 4,554
Likes: 35
From: Godfrey IL
Brake fluid does absorb moisture with age and then this lowers the boiling point. If and when it gets that hot, air forms and air is compressible, thus no brakes. A few years ago I had a ten year old motorhome and the original fluid. I boiled the brakes going down a series of hills in Nevada, E ticket ride, barely stopped her. Changed the fluid, it was very dark, good as new now. I suck out the reservoir first, then fill with clean and bleed out the rest. There is other pressure methods but this you can do in the garage.
It (the water) boils forming steam bubbles allowing the peddle to go to the floor. Brake fade.
Depends on where you live. More humid and chilly, about every two years. I don't go by mileage... weather conditions