Brake fluid reservoir exploded and shot fluid everywhere

[Spike00513]

I am seeing these fail a lot...and I hear this is common...

I want to keep mine from failing. I'd hate to barely pressurize the system to bleed my brakes a year from now, and have the thing explode or leak.

So I guess the only real solution is to replace it, rather than try to reinforce it with epoxy...

I believe the new part is clear, and when they get old (such as our factory/stock part which is 10 years old with ~100k mi), they turn yellow and dry out, resulting in rupturing/cracking/failure. I believe that heat from the engine bay and hygroscopic characteristics of the brake fluid only accelerate the process.



So...who here has replaced theirs? Where did you get it? What do you all think?

It seems like Partsgeek has it for cheapest, @ $100 shipped. A tough pill to swallow, for a little piece of plastic. The part number is 8E0 611 301 G. I am unable to get the GAP price, it appears their website is down.

I THINK that this is the only part needed to do the job, and that everything else can be re-used - such as the bolt that secures it into place.



I wonder if there is another, better part, that can fit...because this one obviously sucks, and like most things in the engine bay, it was made out of plastic to cut costs. Well sure, plastic is light, but would it really be THAT much heavier if somebody like GruvenParts made us an aluminum version? I think it would look really good...

[HalfCat]

[onceover]

Never heard of one cracking/exploding...

[Timtheguru]

It's a common thing on Earth.

[BlazinB5]

[csosnowski]

The rain tray sort of protects the brake reservoir from engine compartment temps. I personally haven't seen a failure but Im sure its possible.

All three of my cars have over 200k and original reservoirs, I now have my fingers crossed.

[Lornnn]

This.

Dude. You come up with all kinds of threads like this. Why?

[Spike00513]

This.

Dude. You come up with all kinds of threads like this. Why?

What do you mean?

[OMG_SHARK]

This.

Dude. You come up with all kinds of threads like this. Why?

Because, he is trying to help the community out. A friend's brake reservoir failed this past weekend when bleeding it. He is just sharing his experience so people won't have to scramble trying to source the part the same day like my friend did. If you don't like the threads that he is creating then don't comment.

[SJorge3442]

hmmm. While I think this is a problem, mine looks pretty damn good. One could argue that you can replace any part because of age and because someone elses failed. Maybe the gauge on your power bleeder was reading incorrectly. I doubt the recommended low pressure hurt the plastic. I could however see a issue if you pump too much pressure into the reservoir than needed. More importantly, change your coolant reservoir.

[Charles.waite]

Because, he is trying to help the community out. A friend's brake reservoir failed this past weekend when bleeding it. He is just sharing his experience so people won't have to scramble trying to source the part the same day like my friend did. If you don't like the threads that he is creating then don't comment.

Really?

Hey my friends car was sideswiped outside my house on sunday, maybe I'll create a thread about how people should be very careful parking on the other side of the street from my house because the sideswiping is rampant. RAMPANT I TELL YOU!!!!! It literally happens all the time (once). I am quite happy that the presumably drunk Seahawks fan that did it spared both my audis and instead aimed for my friends crappy 2003 Outback Sport.

In all seriousness, I've never once heard of some epidemic of exploding brake fluid reservoirs. I've bled mine with a pressure bleeder multiple times as have numerous other friends with similar vintage cars and not one has experienced any sort of failure. Its just not a thing that happens or is very common.

[Spike00513]

Really?

Hey my friends car was sideswiped outside my house on sunday, maybe I'll create a thread about how people should be very careful parking on the other side of the street from my house because the sideswiping is rampant. RAMPANT I TELL YOU!!!!! It literally happens all the time (once). I am quite happy that the presumably drunk Seahawks fan that did it spared both my audis and instead aimed for my friends crappy 2003 Outback Sport.

In all seriousness, I've never once heard of some epidemic of exploding brake fluid reservoirs. I've bled mine with a pressure bleeder multiple times as have numerous other friends with similar vintage cars and not one has experienced any sort of failure. Its just not a thing that happens or is very common.

Cool story bro.

Google Audi and VW brake reservoir crack.

Why the hell do you think I made this thread. I wanted to find out how many B6'ers have experienced this. I don't give a shit if you change yours or how carefully you park the car on the street. I am sorry that somebody pissed in your cheerios.

hmmm. While I think this is a problem, mine looks pretty damn good. One could argue that you can replace any part because of age and because someone elses failed. Maybe the gauge on your power bleeder was reading incorrectly. I doubt the recommended low pressure hurt the plastic. I could however see a issue if you pump too much pressure into the reservoir than needed. More importantly, change your coolant reservoir.

The pressure gauge was correct. It exploded at 10PSI. This is a common VAG failure point judging by what I've read about other cars experiencing this (B6, B5, Passat) and the shops I have talked to. I already changed my coolant reservoir. I am warning you all and providing you with information. Do with it what you like.

-----------------

Now you all know, at least wrap the reservoir in a thick towel just in case it explodes, so that way you aren't scrambling to flush it clean with water in hard-to-reach areas like behind the ECU.

Maybe this is something we should consider replacing. Or at least those of us who can't afford down-time on the car. It is a special order dealer-only part. I'm not telling you all to do this. Again, I don't care. I'm asking what you think. I'm asking if anybody else here has had this problem. Oh well.

[Charles.waite]

According to some shops every single part on our cars are a common failure point.

[Spike00513]

According to some shops every single part on our cars are a common failure point.

Your brain is a common failure point

[Let it snow]

Wow time to end this thread

[BlazinB5]

Because, he is trying to help the community out. A friend's brake reservoir failed this past weekend when bleeding it. He is just sharing his experience so people won't have to scramble trying to source the part the same day like my friend did. If you don't like the threads that he is creating then don't comment.

it's one thing to help a community out, and another to worry about every little thing on a car, just because one person in the entire B6 community had something fail - which doesn't mean everyone else in the B6 community needs to panick/worry about a rare problem. i've had a B5 A4 hit 200,000 miles before i sold it, and my wife currently has a B6 with 210,000 miles - neither of which have had any issues relating to the brake fluid reservoir. Yes, eventually the coolant reservoir cracks, but I've never heard/seen a brake reservoir do the same, yet..

Really?

Hey my friends car was sideswiped outside my house on sunday, maybe I'll create a thread about how people should be very careful parking on the other side of the street from my house because the sideswiping is rampant. RAMPANT I TELL YOU!!!!! It literally happens all the time (once). I am quite happy that the presumably drunk Seahawks fan that did it spared both my audis and instead aimed for my friends crappy 2003 Outback Sport.

In all seriousness, I've never once heard of some epidemic of exploding brake fluid reservoirs. I've bled mine with a pressure bleeder multiple times as have numerous other friends with similar vintage cars and not one has experienced any sort of failure. Its just not a thing that happens or is very common.

this^ x666

[tchuck]

Your brain is a common failure point

Bwaaahahahahhahhaha. That's funny because it's true.

[Charles.waite]

Your brain is a common failure point

Bwaaahahahahhahhaha. That's funny because it's true.

[evo_ski]

Your brain is a common failure point

May want to pump the brakes on personal attacks. Pun intended.

That being said, I have been on this forum for 4 years now and have not heard of a single issue in regards to a cracked or broken brake fluid reservoir. Can it happen? Sure. Is it likely in my estimation? No. If it were likely I would have seen a thread or post about it by now.

I am not saying it is impossible, but I am not going to panic and park my car until I replace it.

[BlazinB5]

May want to pump the brakes on personal attacks. Pun intended.

That being said, I have been on this forum for 4 years now and have not heard of a single issue in regards to a cracked or broken brake fluid reservoir. Can it happen? Sure. Is it likely in my estimation? No. If it were likely I would have seen a thread or post about it by now.

I am not saying it is impossible, but I am not going to panic and park my car until I replace it.

bingo.. /end-of-thread

[tchuck]

May want to pump the brakes on personal attacks. Pun intended.

That being said, I have been on this forum for 4 years now and have not heard of a single issue in regards to a cracked or broken brake fluid reservoir. Can it happen? Sure. Is it likely in my estimation? No. If it were likely I would have seen a thread or post about it by now.

I am not saying it is impossible, but I am not going to panic and park my car until I replace it.

Just to throw this out there, plastic and rubber do deteriorate over time, and that process is expedited by extreme temperature fluctuations. They become less pliable, lose their elasticity, and eventually crumble. My injector harness jackets fatigued to the point of disintegration roughly nine years after they were installed. Coil pack harness lasted a little over ten years. Parts like these don't have infinite service lives.

Our cars are all aging together and some are subjected to more harsh environments than others. Just because no one else (or not many others) has experienced this issue yet doesn't mean they never will.

[redline380]

In OP's defense, I think he meant the reservoir fails when you use a pressurized bleeder. They can only take so much.


In everyone else's defense, don't be a dumbass and put too much pressure in the reservoir. I myself have never heard of a failed reservoir except while using a pressurized bleeding system. And thats just because people put too much pressure in it, not because the tank is old.

[csosnowski]

In OP's defense, I think he meant the reservoir fails when you use a pressurized bleeder. They can only take so much.


In everyone else's defense, don't be a dumbass and put too much pressure in the reservoir. I myself have never heard of a failed reservoir except while using a pressurized bleeding system. And thats just because people put too much pressure in it, not because the tank is old.

Agreed.

We've done dozens of brake bleeds in the shop with a motive bleeder on b5, b5.5, b6, c5, c6, etc. and not had any issues.

The moral of the story is to be careful when using power tools. You'll put your eye out.

[Spike00513]

Oh yeah? Well I've done two million brake bleeds.

In two years, our reservoirs will all explode.

A brake bleeder is not a power tool, buddy

I didn't over-pressurize, under 10 PSI is not too much. They SHOULD hold 29PSI. The factory procedure for bleeding the ABS block with the VAG/VAS tool is at 29 PSI, which is what my B6 can handle. Whereas some cars with the same exact reservoir, explode at just 3PSI (I've heard), and at 10PSI (saw it myself). Many shops, and I too, bleed at 0-20PSI. The motive power bleeder asks you to check for leaks at 10 PSI...

You can always gravity bleed, but that doesn't work if their is air in the ABS block. Maybe a good pressure bleed gets more air out than a long gravity bleed too, IDK. But I generally prefer to spend 30 minutes bleeding brakes, and not 3 hours.

This just in - B6's have been spontaneously combusting everywhere. Make sure this doesn't happen to you. Lube your lock cylinders. I used this stuff on my B6 after being happy with their multi-use teflon lubricant (use it on motorcycle drive chains and door hinges). It gave my B6 50 more horsepowers.



Make sure to use elbow grease

[CyberPMG]

Having been here for 10+ years, this is the first I've heard of the brake fluid reservoir exploding. Congratulations on being the first to report it here.

I have over 281k miles on my car and still have the original brake fluid reservoir. No signs of cracks or leaks.

I have replaced the coolant reservoir when I had to change out the engine some 40k miles ago.

Not saying it couldn't happen since it did happen to you. I've heard of more issues with the coolant reservoir than the brake fluid reservoir. YMMV

[redline380]

Oh yeah? Well I've done two million brake bleeds.

First off, no, you haven't. Lets say each one takes 10 minutes, which is very conservative. 10 minutes x 2,000,000 = 20,000,000 minutes spent doing brake bleeds.

60minutes/hr x 24hrs/day x 365.25 days/year= 525,960 minutes/year. 20,000,000mintues/525,960minutes= about 38 years spent bleeding brakes. Not a chance in hell.

In two years, our reservoirs will all explode.

And if you haven't already lost all credibility, this seals the deal. Never argue a slippery slope. All I have to do is give you one example of a reservoir not exploding in two years, and you are wrong. Plenty of B5's are still on the road (mine included!) without ever having damaged a reservoir.

[SJorge3442]

Spike, this thread has reminded me to replace my coolant tank! Mine is bulging like crazy! Maybe its why my coolant temps are running high (210-220). either way, thanks for the reminder. $26 well spent at RockAuto for a URO tank.

[walky_talky20]

Not to add to the war, but I am aware of the issue with Audi brake fluid reservoirs. I have seen it on my own B5 as well as at least 1 C5. On my own car, I noticed this when removing my reservoir during my 5MT swap. The plastic was cracking and breaking with my bare hands.

The problem seems to be created by UV damage of the plastic due to sunlight hitting the reservoir directly. This happens because the reservoir is directly exposed along the rear opening of the hood, near the windshield. A minor design flaw, really. A little bit of black plastic to shield it would have likely prevented the problem entirely. I would assume cars in more sunny areas that are not kept in garages will be more susceptible to failure.

[CyberPMG]

Not to add to the war, but I am aware of the issue with Audi brake fluid reservoirs. I have seen it on my own B5 as well as at least 1 C5. On my own car, I noticed this when removing my reservoir during my 5MT swap. The plastic was cracking and breaking with my bare hands.

The problem seems to be created by UV damage of the plastic due to sunlight hitting the reservoir directly. This happens because the reservoir is directly exposed along the rear opening of the hood, near the windshield. A minor design flaw, really. A little bit of black plastic to shield it would have likely prevented the problem entirely. I would assume cars in more sunny areas that are not kept in garages will be more susceptible to failure.

Wouldn't the cowl cover help to solve UV exposure? It has a circular opening to get to the cap on the reservoir and only exposes a little bit around the cap. I know not all B6 A4s got them when new, but that cover is available and not that expensive. Cleans up the look of the rain tray as well.

[walky_talky20]

The cowel cover should help. The B6 reservoir itself is also reshaped to reduce the part that hangs out toward the windshield, which should also help.

As you can see on the B5, even with the rain tray, the reservoir is very exposed:



Compare to B6 (3.0 cabriolet shown):



Shows the different shape of the B6 reservoir:

[Spike00513]

The problem seems to be created by UV damage of the plastic due to sunlight hitting the reservoir directly. This happens because the reservoir is directly exposed along the rear opening of the hood, near the windshield. A minor design flaw, really. A little bit of black plastic to shield it would have likely prevented the problem entirely. I would assume cars in more sunny areas that are not kept in garages will be more susceptible to failure.

Are you saying that we should be like sport-bike riders and wear wrist-bands on our reservoirs to protect from UV?

[Timtheguru]

Plasti dip it ;)

[PreciseD]

Are you saying that we should be like sport-bike riders and wear wrist-bands on our reservoirs to protect from UV?

That is to prevent leaks from hitting your visor, paint or worse dripping onto the tires during a race. All other applications are purely aesthetic.

[redline380]

That is to prevent leaks from hitting your visor, paint or worse dripping onto the tires during a race. All other applications are purely aesthetic.

Drift cars do this too since they are always sideways and everything is sloshing around.

[diagnosticator]

OFF topic, Audi owns Ducati.

[SlickFix]

Am I the only one who has difficulty reading the brake fluid level on the reservoir? I swear, that thing is almost as difficult to read as the stupid oil dipstick on my 3.0.

[evo_ski]

Top tip: put a flashlight on top of the reservoir shining into it. It illuminates the fluid inside and you can see it a lot better.

[SJorge3442]

Am I the only one who has difficulty reading the brake fluid level on the reservoir? I swear, that thing is almost as difficult to read as the stupid oil dipstick on my 3.0.

Just pop the cap off and check. if its at the top of the filter, you are good to go.

[walky_talky20]

Top tip: put a flashlight on top of the reservoir shining into it. It illuminates the fluid inside and you can see it a lot better.

Bingo. Works good for murky coolant bottles, too.

Are you saying that we should be like sport-bike riders and wear wrist-bands on our reservoirs to protect from UV?

Due to the shape, I think a "beanie" hat might work better. Oh no, I sense a new fad coming on.

[SlickFix]

Just pop the cap off and check. if its at the top of the filter, you are good to go.

Yeah, that's how I've been doing it. But evo-ski's method is brilliant. I wish I was as smart as he is. I also wish I had his car. In fact, if he has a girlfriend/wife, I'd probably covet her, too!