Brake flush every two years?! U'r kidding right?
 

I was analyzing this over the wknd. Stealership recommends brake flush, here I have read brake flush every two years... etc. Not sure what MB recommends or what is in my svc book in reference to this.

Why if Mercedes supposed to be such a sturdy and durable car, does it require this and has other little quirks that other cars don't have?

I was comparing my former car, 1974 Pontiac... that car's odometer has rolled over twice, so it has about 180K miles, wait rolled over once.. so yeah 180K miles.... Its been in the family for about ten years and never have we changed the brake fluid... wtf? And yeah I agree on the other fluid changes (tranny, rear , oil, coolant, etc.)...

is it a manufacturing deficiency that our brake systems have that require this ? Or?? thanks:confused: :eek:

These cars can be expensive to own - depending on your financial situation.
deal with it and please stop complaining. if the 1974 pontiac is so good, just drive that one and leave us alone. so maybe the brake system isnt the best in the world. who really cares? just do the flush, and forget it.

thanks.
peter

It isn't that the brakes aren't any good -
 

You need to flush the brake system to remove moisture and other debris that can accumulate over time. This is a good procedure for ANY car, not just M-B.

I wouldn't want to see what the wheel cylinders look like on that Pontiac....

just my $.02,

Wes

The brake flush should be done on all cars every couple years to insure you get the longest life out of the calipers as possible.

Someone woke up on the wrong side of the bed today, LOL You didn't really give us any positive input... so why do we have to change every 24 mths? Tell us......:p :p :p "leave us" ? Hmm... didn't know the forum had changed ownership over the wknd.. LOL:rolleyes: :rolleyes:

the boiling point of brake fluid decreases over time because it absorbs moisture. new fluid may boil at 400 degrees, while the fluid in your pontiac would probably boil at 220. if you were descending down a mountain road, your pontiac fluid would boil and you'd fly off the mountain, while the benz with new fluid would be fine. fluid costs like $10 for the good stuff (ATE) and you can get a vacuum or pressure bleeder for $20-45.

Re: It isn't that the brakes aren't any good -
 

Not causing waves or anything, but I asked someone else who was a mechanic for a few decades (not mercedes) and he said he never has had to flush brake fluid just for the flushing.... like an oil change... I mean that master cylinder is sealed tight, if not your brakes would not hold pressure, so how could moisture leak in? If it does, then you have a bigger problem, no?

We're not talking about it being an issue of money, so please don't read between the lines. Just durability, I guess. Complain? Now that I have a 95 E320 , that is the best car in the world, tommorrow when I have somethign else THAT will be the best car in the world, LOL... I have no complaints, just like spearheading good and bad.... I am not like most "enthusiast" owners of any make that scoot deficiencies under the rug mat:cool:

You do not need have to flush out every 2 years, it is just a recommendation.

But brake fluid is hygroscopic in that it will absorb moisture (via the breather hole in the reservoir) over time, the more time the more moisture. Now moisture has 2 bad effects in the brake system, it will encourage corrosion - pistons and cylinders which will be a problem in the medium to long terms. But right now that wee bit of moisture could prove to be a killer - you see if you are using the system hard and system temperatures rise (as they do!!) that moisture turns to vapour which means you foot will go flat to the floor and in the worst case you (and others ) may end up totalled. The hydraulic principle relies on the near incompressibility of liquids once you have vapor then it will compress rather than move pistons and pads.

Your choice at the end of the day. It is a relatively straight forward procedure to do yourself. The guys your side of the pond favour a power bleeder. A search on this forum should turn it up.

NormanB

Re: Re: It isn't that the brakes aren't any good -
 

The brake reservoir is at atmospheric pressure at all times and just provides a small head to the master cylinder where the pressure is developed. The piston being moved to develop this pressure is actuated by your boot and amplified by engine vacuum in the 'booster'.

Have fun.

sorry - yes, youre right, im not in a very good mood today. as for positive input, i dont know a lot about brakes, but it seems that any recommended service should probably be done. i know it gets expensive (ask me, im a college student), but it seems that the risks outweigh the annoyance.
i probably dont read all of your posts, but the ones i have read all have something negative to say about these cars. ill be the first to admit that im not always extremely happy with my car, but overall i think they are quite good and nice to drive.
now, back to the actual technical advice...

sorry again
peter

Re: Re: It isn't that the brakes aren't any good -
 

The master cylinder is not sealed tight and it doesn't have to be from the standpoint of having a system that stops the car. You can leave off the cap and the brakes will work as they should until the fluid sloshes out and/or the fluid abosrbs enough moisture to make it useless.

You do what makes you comfortable. It seems everyone except the folks who write owner's manuals say to change oil every 3000 miles. You choose who you want to believe.

Are you next going to jump on MB for recommending power steering fluid flushes when few if any other manufacturers or independent mechanics agree? Is it ludicrous to have a power steering fluid filter? :)

BTW, I hope SteveB doesn't see this thread.

Sixto
95 S420
87 300SDL

yosshimura, it's your car and you can do the manufacturers maintenance or not, but I tend to trust the folks in the white lab coats in Stuttgart over "Al" or "Larry" down at the local garage working on Pontiacs. Any mechanical device will benefit from regular and thorough maintenance, perhaps that would explain why my 19 year old W201 is still a joy to drive.

Re: Re: Re: It isn't that the brakes aren't any good -
 

MB's have historically been engineered and manufactured with the idea that each car will run safely and soundly for 10 years or more, certainly more. The quality is pervasive, and most likely a big part of why we all like them so much. MB's are also mechanical devices with many moving parts. In order to keep this mechnical device operating safely and soundly for the ages, routine maintenance is a necessity, as it is with any mechanical device. Brake fluid, power steering fluid, etc. are all part of the equation.

Kudos to MB engineers and management to recommend maintenance items that other manfacturers choose to ignore. It speaks highly of their opinion of MB owners.

For cars built of lesser quality, it may not matter if the power steering fluid is changed, for instance. Given the limited life span of most cars on the road today, there may only be a marginal benefit to peforming such maintenance. However, in order to maximize the quality inherent in an MB vehicle, such maintenance is time and money well spent.

I'd say the 'normal' mode of operation for most people is to simply wait until some brake component fails, forcing the matter of a flush. Heck, many treat their gearboxes and transmissions, and cooling systems like that too. I'd say at least most folks are aware of motor oil changes...

The thing is, given a reasonable flushing interval, brake components can last indefinitely.

IMO, the flush will save you money in the long run, and keep you ON that mountain road...

The brake flush keeps you from having to replace calipers in my opinion.

I believe the ABS system is more sensative to old moist brake fluid.

Here's how I look at it...

The single largest cost of buying a Mercedes is the depreciation. After that, we lay out cash for gasoline and insurance. Lastly, we have maintenance and repair costs. On a per mile basis, changing the brake fluid and coolant every other spring is cheap. REALLY cheap in the grand scheme of owning one of these cars.

I reduce my operating costs by doing most of my own maintenence, but the other reason is so I know the work is done to my own standard.

Our own 190E is 15 years old. It runs great, and is a great car. It's not worth much anymore, but through MB's maintenance regiment, we've got nearly 400,000km's of solid running out of it, and it has many more miles left.

It works.

When you compare how the brake fluid looks, after only a year, to new fluid, the answer is pretty obvious.

Brian

Hey yosshimura, Don't flush your brakes for a couple of years. Then bring it in my shop for repair. Reading your posts seems like you are always complaining and whining about mb's. You always complain about Mb's dealerships, shops and services. You need to get rid of your Mb and get a corolla or honda, even a Kia would seem to fit you properly. Then you can also get rid of that fake rolex and get a real one.

LOSER

Jerry... its all right to be pimpin' on a budget;)

I can tell you that the brake fluid on my 86 560sl, which had supposedly been serviced 6 years earlier, looked like rusty milk. Worse, I had to replace all four (4) calipers. One was totally frozen, 1 was very stiff and I'm sure was going to fail in the next several months, and the back two were found to be seriously pitted after I had disassembled them (with great difficulty) for inspection.

The prices for NEW calipers are eye-popping. I don't think you could get 4 for under $800 and never mind the PITA/expense of installing them. I got rebuilts from advance auto (so far, so good). So, especially if you do the fluids yourself, preventative maintenance can be a money saver.

Now, as far as the safety is concerned; what you have read about boiling points and the hygroscopic nature of this stuff is true (I read up on this because I couldn't beleive it either). Your brakes will NOT be as good in an emergency if you don't change the fluid every few years, never mind the corrosion issue. This isn't a property unique to MB cars and brakes.

Very new cars may be using a newer fluid, which is much better and not as hygroscopic Unfortunately, as far as I have read, you can't just replace the older-style fluid with this stuff unless you have the whole thing professionally flushed, which is probably beyond my MITIVAC. There may also be compatibility issues with the rubber hoses.

It seems that the original question was why does MB recommend flushing the brake fluid while other manufacturers don’t? The inference being that this must be due to an inherent weakness in MB’s brake system. I think enough information has been provided on this thread as to what happens to brake fluid overtime. The weakness is in the nature of break fluid as the two links below explain. If other manufacturers choose not to recommend flushing then that’s their problem not MB’s for failing to alert their customers. From a business standpoint it makes sense. They get to replace a lot more expensive brake parts than MB owners, who flush their brakes biannually, do. Is MB at fault for alerting their customers or are the others at fault for not including this straightforward procedure as part of their regular maintenance program?
http://www.osbornauto.com/questions/bfluid.htm
http://www.rpmnet.com/techart/fluid.shtml#fluid

yosshimura hs a point. His Pontiac is running fine and the MB needs brake fluid changes. My Volvos need brake fluid changes too. The reason the Pontiac doesn't require brake fluid changes is because the master cylinder has a bellows built in to the seal between the master cylinder and the cover. As the brakes wear and the fluid level decreases, the bellows is drawn down.

European cars have a vented cover, the older American cars don't. Perhaps the newer American cars do. Those cast iron master cylinders sure were heavy.

yosshimura, your 3.2 engines requires 7-7.5 Qt of oil, vs a GM 3.4 engine which requires 4-5 Qts.

More oil means that the percentage of contaminants is less.

Is the brake fluid capacity higher for an MB vs other makes?

But not much of a point.

Brake hoses are made of rubber too and they allow air/moisture to migrate across cell boundaries.

Also, most motorcycles have a similar brake reservoir arrangement to the one you describe - and I can only speak about Suzuki here - but they also recommend 2 yearly fluid changes.

As I posted originally, it is only a recommendation but - there is a horrible cost in finding out you made a poor judgement call in saving $30 or so!!

I would be willing to make a VERY LARGE bet that your 75 Pontiac, or whatever it was, has not gone almost 30 years with no brake hydraulic attention.

My MB's, with annual brake flushes on the other hand, have never had any hydraulic attention and still work fine.

As stated earlier in this thread I'm sure, brake fluid absorbs moisture, moisture makes corrosion. Regardless of what you drive you have two choices. Flush brakes annually, using $2.00 or less worth of brake fluid, or periodically do expensive brake hydraulic repairs. Your choice.

Have a great day,

Two additional small points:
 

1. German cars, not just M-B, have service recommendations which assume they will be driven under autobahn conditions, which means the manufacturers have to be concerned about the effects on brake fluid of repeated stops from very high speeds. Extreme hot and cold cycles do increase the hygroscopic rate of the fluid. Mountain drivers, take note.

2. Water absorption in humid climates, obviously, is a bigger issue than it would be in the New Mexico desert or in a very cool but relatively dry climate. We never had big rust problems with old brake fluid when I was a kid in Minnesota, but here in Tidewater Virginia, I would definitely follow the every two year recommendation, as I would if I were forced to live in Florida.

Therefore, you can apply a certain amount of critical judgement to the brake fluid change interval, but you'd better be sure that you really know what you are doing. It is also true, as someone else suggested, that old Pontiacs' service schedules assumed that the brakes would wear out often enough that the fluid would be changed as part of wheel cylinder rebuilds every couple of years. For those who just threw on a new set of shoes without even looking at the cylinders, this could be disastrous.

Fimum Fit,

You bring up a very logical point. In the drum brake days it was just common knowledge that when you replaced shoes, you cleaned, honed and replaced the kits in the wheel cylinders. If you didn't it was a virtual guarantee that you would be doing so soon afterwards.

Those cylinders pitted like crazy. Most calipers have stainless parts and the seal is in the cylinder rather than on the piston, or at least move with the piston.

Even with those old systems, annual brake flushing would have kept them in much better shape, and required much less trouble at brake time.

Have a great day,

Brake fluid has to be changed after some interval, longer or shorter, all fluids in the car do.

All German manufacturers require the brake fluid change to be done each 2 years, even in the old VW Bugs(drum brakes all around) the recommendation was the same. In my 1966 Bug(now in repairs:( ) I've not changed it for 2 and a half years, not even completed in the meantime, and when I've looked at the reservoir, the liquid inside was black. Not "a bit rusty", like others say, but black like sewage. Obviously I've drained immediately the brakes and refilled...

Conclusion: you may change the fluid in the Pontiac or Mercedes, or you may leave it as it is. It's your risk:D

~Nautilus

But they do exist.

If you think about the physics of how the master cylinder creates pressure within the brake lines, there is no way that it can be air tight.

Also, rubber brake lines are not completely impervious to moisture seeping through, and given brake fluid's love of moisture, a great deal of moisture can be transfered through the rubber lines.

We change our oil on a regular basis, lovingly caring for our engines. We fret over tranny fluid changes, hoping to keep that beats shifting into old age. Why make the mountain to die on brake fluid? Even having the dealer do it, it's a cheap job.

I'm not sure about you guys, but brakes are kinda important to me. I keep my brakes in top shape, and the tires under them as well. Those are two areas I don't let slide.

I don't know how important it is to flush the brake system as recommended by Mercedes, but I can tell you that I have followed this routine (along other "stupid" routine Mercedes has recommended) and I still have the same original/unopened brake calipers, master cylinder and brake lines that were installed on the car back in 1989....15 years ago and 380K later.
JackD

Yeah I know where you are coming from ;-)

.........and I agree with you. :-)

One thing though this thread certainly attracted attention :-)

It has been a good discussion.

I too have applied the Mercedes regiment to our other cars. I use Mercedes coolant in our other cars, change the brake fluid every two years, and so on.

Guess what? It works. On our other makes, I constantly have mechanics that are amazed at the usefull life we extract from them. I attribute it solely to using the Mercedes maintenenace regiment.

I think it's more a matter of most non-euro OEM's don't care or don't figure anyone is gong to bother dong maintinance like that so they just save the ink in the book. What does a person who buys a 94 for instance pontiac do as soon as it's out of warranty?
Take it to the cheapest place and do as little as possible and drive it till something really $$ breaks, then sell it. Or they trade it in on something still under waranty. This is the way cheap cars and cheap people generaly work. I deal with them every day of the week. I constantly replace master cylinders, calipers, radiators, transmissions, engines, anything and everyithing of late 90's cars with barely 100K on them. It's pathetic.

As others said, if you follow the common sense MB maintinance practices on other vehicles, you'll get simlilier results. I was doing this pretty much before I had ever driven an MB.

Glad to know you think of yourself as a looser, LOL.:p

What trip, I am out for a couple days and have three pages to read. I will read tonight and respond. Thanks for the positive and not so positive comments :) / :rolleyes: .

I just shoot straight. If I Pay $4.1K for a Rolex and think it is just a good $1k watch I say it.. I don't have none of my material things up my butt.

Don't get me wrong I love my car... no regrets, no dissapointments, no.......... going home, to be continued.

The answer to all of your questions
 

Here is an article on brake flushing and should answer all of your questions.

http://www.brakeandfrontend.com/bfed1.htm

http://www.brakeandfrontend.com/bfed1.htm

Thanks for the info Larry. Again, i am just making a point not whinning, as no one forced me into mercedes, lol.... And remember this is the second Mercedes I have had. As someone mentioned maybe its the type of master cylinder with ...ugg I forgot, that rubber thing going down into the fluid (on the cap) or who knows... I had gone through the maintainance requirements b4 so its not like I am going to forego anything on the schedule.

As for the Pontiac... Its been in the family for about 180k miles, 15 yrs or so, uncle # one bought used 15 yrs or so, then uncle #2 had it, then cousin # 1 had it, then me for the last 10-12 months. I asked uncle #1 and he said he never changed the fluid. I have to confirm with #2. Its a matter of interest at this point.

As for the other poster mentioning how the brake fluid looks after x miles.... have you looked at your oil, just after starting, when you change it, it is pretty, but not as pretty as when it was pouring out of that bottle, lol.

I am changing tranny / rear end / brake fluids in the next 60 days anyway.. whatever the answer would've been, as to keep up with the maintainance the car had in its previous life.

thanks:cool:

The difference is that the European automaker philosophy is to make a car that if maintained properly, will last 20 years. The American automaker philosophy is to make a car that will last for the duration of the warrantee, then it can be thrown out.

Your mentality is exactly why American automakers don't recommend it. The average American auto buyer looks at the service recommendations and says, "Geez, that MB needs a lot more service than that Chevy... I guess I'll buy the Chevy." So they're encouraging you to maintain your Chevy poorly, and you're rewarding them by buying a Chevy every 5 years.

Yet another symptom of our pathetic throw-away society.

(In my humble opinion)

Jeff Pierce

The links above show - very graphically! - why we need to flush the brake fluid every 2 years (or better yet, every year). The fluid should be golden in color - not brown. I have a Speedi-Bleed kit which makes the flush procedure a snap. Even paying the dealer is only $50 - much cheaper than replacing or rebuilding calipers, master cylinders, or ABS pumps. (You *did* look at the link Cigar Havana posted, didn't you?)

On a side note, MB specs a DOT4 fluid. I did a ton of research on brake fluids and the short version is to use Valvoline SynPower fluid, it has very high boil points (above DOT 4 specs), is easily available at every McParts store nationwide, and only cost $5/quart. Yes, ATE SuperBlue (and Typ200 Gold) is better... but it's harder to locate and costs $10-$12/quart. I prefer the ATE but the Valvoline completely outperforms any other cheap fluid on the market. Just make sure you change it at least every 2 years!

:cool:

Ooooh... I feel a brake fluid thread brewing...

Sixto
95 S420
87 300SDL

Maybe we could discuss the merits of synthetic brake fluid compared to good ol' dino?

(struggles to keep straight face)

:p

Sixto, you may be on to something - brewing our own brake fluid..:D

Cheers,
Wes


(Let's see, it will need to strip paint. Also be able to absorb moisture.... anything else?)

Do NOT mix SynPower with any other fluid. I have had some weird results. You must flush all the old stuff out when you put in Syn Power and you better keep some in the trunk when you want to top it off. It seemed to me like it seperates and doesn't mesh uniformly with the other fluid if you add other fluid to it.

I prefer ATE Blue for my gas powered cars and ATE SL for my diesels. I change it about once a year in the spring or so like MB recommends.

Interesting. Why?

Sixto
95 S420
87 300SDL

Diesels dont go faster than 100 mph, and if you let off the throttle and turn on the power emergency brake (the AC), usually you can stop pretty easily, so you dont need to stop too hard too often so ATE SL fluid offers a great b.p. for this car.

In Gas cars (MB) usually you drive faster than 100mph and you typically slam on the brakes, so you need a higher temperature fluid, that is why I choose the ATE Blue.

Interesting note about SynPower blending. I didn't see any warnings on the label, I think they claim it works with all fluids? Anyway I pressure-bleed and flush everything out so I have all the same stuff through the whole system...

:)

K good, I think I told you about that before! :D

My 2 cents worth..

Interesting site...

...fluid

Not sure i agree my self but thought id share the info:)

From the MB Club UK:)

1. Hi.
2. Please enlighten us what do you not agree with and why?
3. For info I cross posted the link on MB Club from here (yesterday evening 7 pm ish) - we really are in a global village.:D

Regards
NormanB