Fluid Change

[Uncle-A]

Changing the oil in my vehicles has been one of the maintenance items I have been very active in following. Recently I was talking to a friend and he said he was going to have his brake fluid changed. In over 50 years of driving I have never done a brake fluid change or have I ever heard of this maintenance item. I have added it fluid when low or bleed the lines of air after changing a master cylinder but never a complete drain and replace. I tend to think of these new items as ways for dealers to inflate the bill. I could not find any reference of a brake fluid change in the owners manual of my truck. So what do the PUGSKI car people think of changing the brake fluid?

 

[Bill Talbot]

Absolutely!
Brake fluid is hydroscopic (absorbs water). Water lowers the boiling point. Water can cause calipers to seize, piston bores to pit, hard line to rust from the inside out, etc. I do my cars every 3 years, motos every 2.
If the vehicle is a keeper, DO THIS! If you trade in or sell every 5 or 6 years it probably won't hurt you yet. This is a very real maintenance item. If you look at your brake master (and clutch master cylinder too) the fluid will get darker
as time goes on. It starts out a very translucent light amber.
It's in every car and moto owners manual I have as well.
btw, you should be following the 'severe service' timeline too

 

[Uncle-A]

Absolutely!
Brake fluid is hydroscopic (absorbs water). Water lowers the boiling point. Water can cause calipers to seize, piston bores to pit, hard line to rust from the inside out, etc. I do my cars every 3 years, motos every 2.
If the vehicle is a keeper, DO THIS! If you trade in or sell every 5 or 6 years it probably won't hurt you yet. This is a very real maintenance item. If you look at your brake master (and clutch master cylinder too) the fluid will get darker
as time goes on. It starts out a very translucent light amber.
It's in every car and moto owners manual I have as well.
btw, you should be following the 'severe service' timeline too

Bill, thanks that is interesting. My truck is a 2006 and I have never changed the brake fluid, maybe I will look in to what is involved with a change. If the brake system is a sealed system how does water get in to be absorbed?

 

[scott43]

Not sealed 100%. Taking the cap off on the master exposes it to atmosphere.

 

[Bill Talbot]

Bill, thanks that is interesting. My truck is a 2006 and I have never changed the brake fluid, maybe I will look in to what is involved with a change. If the brake system is a sealed system how does water get in to be absorbed?

The reservoir is vented to ambient.(some use a rubber bellows against the fluid and the top of that is vented) It has to be for the master cylinder to function properly. As your brake pads wear it will draw in fluid to push the caliper piston(s) further out. If it was sealed that would create a vacuum above the fluid, which would mean less head pressure. Also when the brake pedal is not depressed a small bleed hole allows the brake system to return to ambient pressure. This same bleed hole will allow small bubbles of any air entrained in the fluid (from boiling or other causes) to vent into the rez.
I'm telling you to look at the color...it IS darker and needs a flush and bleed with new, from a sealed bottle of DOT4 brake fluid.

 

[raytseng]

I suppose the one fact to be aware of, is the tradeoff of the higher peformance DOT4 type fluids has lower life span than DOT3 type fluids.

So unless you are racing or need sustained high temp brake performance, go with the lower spec fluid as it will last longer (more water holding capability).
I believe the recommended intervals are DOT3 3years vs DOT4 2years.

 

[crgildart]

I was once at a service center in line behind a woman who was asking if they could "change the air in her tire".???? Everyone was like... "WAAAAAAAAAT???????" English wasn't her first language.. She had a flat..

 

[Uncle-A]

I suppose the one fact to be aware of, is the tradeoff of the higher peformance DOT4 type fluids has lower life span than DOT3 type fluids.

So unless you are racing or need sustained high temp brake performance, go with the lower spec fluid as it will last longer (more water holding capability).
I believe the recommended intervals are DOT3 3years vs DOT4 2years.

I have always used the DOT 3 fluid, but my 2006 Truck is the newest vehicle I own. I will have to go back and check the owners manual if DOT 3 or DOT 4 is required.

 

[crgildart]

Why wouldn't they drain and replace your brake fluid when you get all 4 rotors turned and new pads all around??

 

[Core2]

Why wouldn't they drain and replace your brake fluid when you get all 4 rotors turned and new pads all around??

No need, just have to replace the lost fluid from the brake bleed.

 

[Bill Talbot]

No need, just have to replace the lost fluid from the brake bleed.

That's one approach.
I prefer to get ALL the old fluid out, then put new fluid in the system. To top of with fresh into a reservoir filled with X years old fluid makes no sense to me...
And since it is easy to do, why wouldn't you?

 

[Eleeski]

What exactly is the degradation that occurs with time? Doesn't replacement on condition make more sense? Certainly replace dirty or burned fluid. But draining perfectly good fluid is expensive, bad for the environment and possibly an opportunity to introduce contaminants.

My cars (and boats, skis and airplanes) are tools to get me places. Not personalities to be pampered. They get what they need and nothing more.

I do love draining the fuel - by running the wheels off.

Eric

 

[Muleski]

For many years I used Ate brand brake fluid in our cars. It's a very high quality fluid, and it used to come in two colors. The typical amber, as now mandated by the DOT, and a "Super Blue." Made it very easy if you alternated the colors with each fluid change to know that you had all of the old out. Man, I miss that. Blue is no longer available in the U.S.

Fluid changes of all sorts is the best maintenance that you can give a car. I did a power steering fluid flush on our Land Cruiser last weekend. Amazing how much more quiet the steering is. Cheap insurance.

Our son and his GF recently bought a new to them car. It's a high end car, with 155K miles.....and perfect service records. Still our son had a punch list to go through, and it started with changing every single fluid in the car. He was frankly amazed at how good everything looked. But even so, the transmission feels better, brakes feel better, etc. etc. The car had the alleged lifetime transmission fluid, which the owner had replaced at 100K. Son is doing a "drain and fill" every 3K for a while. Has done his first two and the fluid looks great.

He's in the Tahoe area. Car is a CA car and the underside looks perfect....for a 2008. That to "wrench" a car like that. He has plenty to do.....basically an entirely new suspension. all factored into the price.

But fluids, and filters done regularly, or more frequently. Yes. I'll take a quality high mileage car with the right maintenance ANY day.

 

[Snowfan]

Replacing brake fluid every 24 months is recommended maintenance of my car. Not sure why, exactly. I would imagine moisture is the primary issue concerning brake fluid, especially so considering ABS components. The ABS hardware makes swapping the fluid out a bit more labor intensive than in the old days.

Same car has zero maintenance schedule for trans fluid and does not come with a dipstick. Methinks they got the 2 confused. I bought a correct "dipstick tool" and swap fluid and filter in trans every 60K miles.

 

[François Pugh]

Agree brake fluid collects water, which will eventually prevent you from making two hard stops in a row. A brake fluid change is cheaper than an accident. I typically change mine when I get the brakes (pads and rotors) done.

That being said, if you drive in these parts, your brake lines WILL rust from the outside and require replacement. If you are using the ROF maintenance method (not recommended), you will be replacing the brake fluid often enough (after it leaks out onto the road through the rusty line) on an old car.

POWER STEERING FLUID?

 

[Uncle-A]

Why wouldn't they drain and replace your brake fluid when you get all 4 rotors turned and new pads all around??

I have not needed to have all 4 disks replaced at the same time. My 2006 112K truck has had the two rear brakes go first and the front about a year later. My 1999 Convertible with 63k has disk in the front and drum in the back. It is a 2 to 1 replacement the disks twice and the drum once, so the second time was all four but still have not replaced the brake fluid. Both have DOT 3 fluid and never changed.

 

[Bill Talbot]

Agree brake fluid collects water, which will eventually prevent you from making two hard stops in a row. A brake fluid change is cheaper than an accident. I typically change mine when I get the brakes (pads and rotors) done.

That being said, if you drive in these parts, your brake lines WILL rust from the outside and require replacement. If you are using the ROF maintenance method (not recommended), you will be replacing the brake fluid often enough (after it leaks out onto the road through the rusty line) on an old car.

POWER STEERING FLUID?

PS fluid is another area of much neglect. Two schools of thought here. One is to suck out the rez at every other oil change and refill with the proper rated fluid. This I can only recommend when starting with a new vehicle. But if you do the first change well into the cars life the fluid is likely very dirty and likely contaminated with metal particles. This would require a full system draining (best when hot) by removing a line. Then the system would be refilled and cycled with the front wheels off the ground to bleed the air out.

Dare we talk about accessory belts/serpentine replacement or even more importantly CAM BELT replacement if your engine has one???

As for 'lifetime fill' in gearboxs/transaxles/differentials, well lets just say that in the manufactures mind, that mean till the warranty ends. If you're keeping the car CHANGE the fluid!