Your mechanic's response to you is very very common. Rarely do people flush/replace the brake fluid unless they replace a part in that system. If you change a caliper , you have to bleed that section of the brake system, but not the others.
I wouldn't try loosening the bleeder screws on those 18 year old calipers unless you want to snap them off. Your choice.

If replacing the brake fluid is a must do for drivers, I would consider doing it on a 5 or less year old car. Bleeding the brakes is easy. It's easier with a helper though.....Keep driving.

 

My mechanic, who I trust very much and is very knowledgeable, said that he's never touched brake fluid on any of the vehicles he's ever owned himself. He said that he typically will only change brake fluid on the cars he services when there's a part of the brake system that is getting replaced.

Maybe your mechanic likes making money replacing brake parts that failed due to fluid contaminated with water. Brake fluid by design is highly hygroscopic the longer it is in service the worse performance and protection gets.

In my experience if you replace brake fluid every 3-5 years components will never go bad unless road salt gets them.

 

On my cars and customer's cars, my rule of thumb is 5 years or 100K if DOT3, 2 years or 25K if DOT4 (only by virtue of cars typically running DOT4 having higher-performing brake systems).

But what I do is recommend it if it isn't translucent anymore. If I can't see the bottom of the reservoir, it's time.

Also, +1 on hygroscopic. A lot of the general-repair mechanics down my street keep open bottles of brake fluid around. "Duhhh...I've never had a problem." If you open a container of brake fluid, you use as much as you need and throw away the rest. If your mechanic is using fluid from an opened container, tell him you want new stuff or find a different mechanic.

 

Hate to brake it to you, but your mechanic either doesn't know what he's talking about, or he makes too much money replacing calipers to tell you the truth.

Brake fluid is supposed to be replaced every 2-5 years depending on car. Sports cars every 2 years, other cars every 4-5.
If not, brake fluid will absorb too much water and will start rusting your whole brake system from the inside.


There are brake fluid testers to test moisture content of the brake fluid - anything more than 2-3% necessitates fluid flush. They're $30-40, and any decent mechanic must have one to test brake fluid for their clients.


If you have not flushed the fluid in 18 years, your calipers will rust on the inside and will seize. You will have uneven brake pad wear and your trusted mechanic will tell you that you need new calipers, even though they may look totally fine on the outside. I have personally rebuild multiple calipers and observed the inside myself.
Then your brake line will burst, again from inside out. It will look fine on the outside but get a hole in it inexplicably.


Another likely outcome: you will get mushy brake pedal. The moisture will boil and turn to get, and your brake pedal will start sinking to the floor. Your trusted mechanic will tell you that you need fluid flushed. Then he'll call you and tell you that you also need new calipers because the bleeder screws have seized because noone ever touched them.


All true stories. Your choice.

 

It depends somewhat on the typical humidity where you live. Dry desert climates can go longer. Humid all the time, less.

 

Hygroscopic brake fluid should be flushed, but you bring up a very good point about your rust issues, Break off a bleeder and you need a caliper, hmmm maybe not. Mercedes recommended replacing the fluid every two years, in the spring, during a period of low humidity.

At 18 years age, I would definitely turkey baster the master reservoir. One time I bought a 94 Honda Civic VX that had been totalled at 27k miles from a yard in Ohio. The car was amazing, since it had sat inside an insurance training center for 15 years. When I pulled the cap off the master cylinder the seal on the bottom of the cap had disintegrated due to the old brake fluid. Never had to replace anything else in the next 40k miles I drove it, but if I had to bleed the master I would have figured on replacing it.

I would not so quickly jump on your mechanics arse about not flushing fluid. Since it is a very neglected preventative maintenance AND opening up the bleeders COULD mean 4 calipers might need replacing as well as the master cylinder AND the ABS module on newer cars, I would personally WARN each customer of the potential consequences of a flush.

After loosing a few master cylinders during brake work, even talking my own cars master off for a customer who could not afford a new one, I think I can clearly see both sides of this discussion and a reputation could be in the balance, when either side has a good pragmatic argument. Thank God I did not live in areas where rust dissolves cars in a decade. WE never pumped the master to the floor when bleeding. It subjects the seal to the bottom of the cylinder where it can pick up contamination and fail right there. We tried to duplicate (to the greatest extent possible) the normal travel, after I had to take my own off and give it to a good customer, who just did not have unlimited funds. She was a really nice looking gal so maybe that was a part of my decision :nerd:.

 

Reminds me of a father and daughter customers of mine. They had restored a 280Z for her to drive, with her helping all the way, She was a stunningly beautiful girl, which amplified my appreciation for the effort by Dad and Daughter.

So what does the friggin car do but THE WATER PUMP DUMPS RIGHT ON THE LIFT IN MY SHOP!!!!! #$%^&*() now I look like one huge piece of shit.

The Father's next comment made me feel like a KING. "I sure am glad it happened here instead of on the side of the road at night and it could have been so much worse." I would have given him the damn water pump after that.

 

"At 18 years age, I would definitely turkey baster the master reservoir. "

I was going to suggest using a hand vacuum pump to suck all the old fluid out of the master cylinder and refilling it to the full line, but a turkey baster will do the same thing. That way you don't have to risk breaking off an 18 year old bleeder screw. I would repeat this procedure 3 or 4 times over several days to get the most dirty fluid out you can.

Mike

PS: I probably wouldn't use the turkey baster for cooking after this procedure.

 

I used a plastic syringe to suck up the fluid from my master cylinder then I added DOT 5.1 instead and bleed out from each of the wheels on my 08 Camry. It took a bit of time but the pedal eventually felt much better than before (this is recently after I did my brakes). My plan is probably once every 100,000 miles BUT if I am bored and need something to do (like I have been doing since the start of this year) it may end up being every 50,000 miles.

Always remember:
DOT 5.1 works with DOT 4 works with DOT 3, don't use DOT 5 as this is a silicone based fluid.

 

I am told that a lot of professional mechanics consider sucking the fluid out of the master cylinder and just replacing what they took out, as a "brake fluid change." I asked the OEM mechanic I know(he is my neighbor), he just smiled and said "no comment."

 

I mean, just the fluid in the res is better than nothing, but it certainly does nothing for the fluid in the calipers and most of the fluid in the lines.


It's simple: change the fluid, otherwise either the calipers will seize, brake pedal will go soft, lines will rust through, or both. Even worse is that if you don't realize your brake pedal is too soft because you've gotten used to it, then you can crash in an emergency because your pedal hit the floor and you can't stop fast enough.

 

My instructor had a good way to describe when you should change your brake fluid and/or master cylinder. It's for that moment when you are stopping from high speed on an off-ramp and your foot just goes dooowwwnnn....

 

I have a glass "syringe" that can not be damaged by any caustic fluid and it stays in the garage. At 19 years age (my Echo) when I replaced the brake pads, I pulled the dust boot back and the outside of the caliper piston was spotless. When you compress the piston to get the new pads to fit you push almost all of the fluid back into the master and I sucked the fluid out after that until I couldn't get any more out of the master reservoir. I did this on both sides separately, something about 68 year old memory makes me more cautious with critical items like brakes.

This is not an argument, more a pragmatic look at what is reality in areas where cars disintegrate, versus here where the bottom of my car has no rust, unless the part was never painted, like a brake rotor and even then mine are painted and cleaned when they are removed at least the mating surfaces with the wheel, of course not the friction surface.

Anyone here take the time to clean the beads of their wheels during a tire replacement? Probably not but when you do the tires hold air like new cars tires. Most techs are just in a hurry to get them on the rim, no time for diligent surface preparation.

As a shop owner my outlook was more pragmatic concerning fluid service intervals, customers driving habits, and maintenance. If you change brake fluid religiously, is it really cost effective? Rotating tires every 5k miles, now that is a waste in my opinion and it can hide other problems. 30 years ago radiators and brake hydraulics were considered to be worn out at 10 years, now they last twice as long. The OP was honest, his fluid was never changed and I doubt it was ever changed in my 19 year old Echo.

Does the fluid at the end of a sealed hydraulic circuit ever see moisture to be absorbed. Moisture that has to travel through many feet of tubing to reach the caliper or wheel cylinder. In my Civic example, even though the fluid had done obvious damage to the reservoir cap, no single component of the rest of the system had to be replaced after another 40 k miles. I sold the car with 60% of the original front pads left at 67k miles. The car was 18 years old when it was sold.

When you start bleeding a complete system AND YOU ARE DOING THAT FOR A CUSTOMER, if you do not warn them of the potential for a very expensive repair that could cost them thousands, how many do you think would authorize that repair. A flush is recommended but it could initiate a nightmare and thousands of money spent. Most people that trusted you completely would step back and say wait a minute, you want me to do this, BUT IT COULD END UP BEING A NIGHTMARE. "I think I'll take my chances and pass up on that." I don't know about others but if a doctor tells me there is a procedure we recommend but it involves risk potentially exorbitant costs and potential permanent irreversible damage, I think I might decide to pass up on that procedure until I better understood the risks.

Now my car has no ABS module so that makes it much less scary to flush fluid, but I have seen the caliper pistons and they are still perfect or I would have cleaned them. Some may say pop them out and clean and reinstall with a seal kit. Bottom line is the turkey baster reservoir drain and fill may be the best alternative, especially for those who want to do their own labor. When the front pads are on their last leg and you are going to compress the pistons, then it MIGHT be worth your while to see if the bleeder is not rust welded to the caliper. I even have a spare master cylinder, vacuum booster, and all the lines and hoses for the brake system, in case something will not come apart.

When I took my parts car apart the brake lines came apart wit ha craftsman open end 10 MM wrench, did not even require a line wrench and no fasteners were destroyed in taking a car almost completely apart, not unusual here at 175k miles but in many areas it would be a disaster if you even tried.

 

When you start bleeding a complete system AND YOU ARE DOING THAT FOR A CUSTOMER, if you do not warn them of the potential for a very expensive repair that could cost them thousands, how many do you think would authorize that repair. A flush is recommended but it could initiate a nightmare and thousands of money spent. Most people that trusted you completely would step back and say wait a minute, you want me to do this, BUT IT COULD END UP BEING A NIGHTMARE. "I think I'll take my chances and pass up on that." I don't know about others but if a doctor tells me there is a procedure we recommend but it involves risk potentially exorbitant costs and potential permanent irreversible damage, I think I might decide to pass up on that procedure until I better understood the risks.

On the flip side, soft brake pedal and loosing brakes are a very real possibility of never changing the brake fluid. There's a very simple solution here: test brake fluid for moisture content and inform the client of what it is and what their options are, and what the possible consequences of not doing the repair are. I have seen honest shops, rare as they are, but that's exactly what they tell you - life left in your brake fluid, exactly how much life is left in your pads, the condition of your coolant from a coolant tester, the condition of your battery from a battery tester. They pair it with their recommendations and leave the choice up to the customer.
I don't think it's right for a mechanic to assume that the customer will run away from the truth so the mechanic should not disclose it. Tell them the way things are and chances are good they will appreciate your honesty more than you think. I have stopped going to some mechanics because they clearly lied to me, but I have never stopped going to a shop because they were honest with me.


And to your argument that your 18yo car had pristine calipers: you must live in a dry climate, and I envy you greatly. Here in north east (op is from NJ, I'm in NY), we're blessed with humid weather that destroys cars with rust like you wouldn't believe it. Just from my personal cars, I've had a brake piston rust almost completely through on my 2002 Celica, it was due to collapse any moment the day I caught it; I've had brake line rust through on a 2002 Mazda, luckily for me it leaked out the brake fluid while sitting on my driveway; I've rebuild plenty of 2000+ brake calipers that were in horrible shape. Heck, last year I had brake pad bind up due to rust and wear down to metal in caliper bracket on a 2012 Civic - the car is 7yo and has under 27k miles! Yea, I treat brakes very seriously.

 

How often do you guys change your brake fluid?

Live in SE US with high humidity, complete system flush and replace every year.


Water in brake fluid is dangerous potential.