SBC Replacement
In order to use the back up system you have to push with both feet. BOTH FEET. And that's right on the very bottom of the stroke.
Think about this the next time you hit your brakes behind a container truck that has it's sharp rear edge at your head level. Or perhaps the next time you have to stop at a railroad track which has a train barreling down at 70 mph.
The removal of the SBC has NOTHING to do with cost reduction. It's because the back-up system is almost useless and brake failures mean multi-hundred million dollar lawsuits.
Don't ask WHY I know all this..........
Last edited by Spartan; Aug 6, 2005 at 03:20 AM.
That is a "Dream Episode" of Dateline.
"They are the finest made luxury cars on the planet, but inside lies a dirty little secret....a secret brake system flaw that claimed the life of a devoted father of 3 and his wife during a night out for dinner"
cut to shot of the kids "I just want my mommy and daddy to come home"
Tonight, we go inside.....Deadly Diamler.....a Dateline Exclusive...next.
It writes itself.
Benz sales would drop through the floor.
We have had a guy on this forum already experience brake failure just like that....thank God he was on a highway and coasted to a stop. Yikes.
You have a few (VERY) isolated instances of failure of this system that are not more, or less frequent than failures of any other brake system is the information that I've been given from a few credible sources... like the DOT (I chatted with an engineer there for about 20 min about the CDI specifically, and SBC in passing), and most of them were on earlier models from 2002/3 and in Europe.
Spartan, I believe you are the only person who had a total failure of this system that I have come across on 4 or 5 different forums on MB (where the loud minority hang out).. and your car was a pre-recall system which was not fixed before the failure, so it's just not fair to pain in this broad brush the entire SBC fleet of E, S and CLS cars.
I flew FBW (Fly-by-wire) jets for 10 years and not once did I worry about a failure just because it was remotely possible... reality is (and SBC is the same) there is redundancy and it's generally statistically impossible to experience a failure on the latest updated system.
Last edited by CE750; Aug 5, 2005 at 09:00 PM.
Two, so far as I know the failures we've heard about in the U.S. were due to the system erroneously shutting down because it thought it had a problem. In every case it appears that was because of inexperienced service personal failing to complete a bleeding process.
Three, the brake recall DID NOT FIX ANYTHING. All that it did was program a counter of brake applications so that the car operator could be given a notice to take the car in for service before the pump wore out. None of us will keep our cars long enough to ever see that message.
I'm not belittling anyone's experiences with an SBC shutdown because it falsely thought there was a problem. The system shouldn't have shut down in these cases and it would not have if the vehicles had not had an incorrect brake bleeding procedure (incomplete bleeding).
Now that dealers know what they are doing (hopefully), there should not be any more of these isolated incidents.
Do I think Daimler-Chrysler are changing the brakes because of cost...yes.
Do I think Daimler-Chrysler are also worried about liability issues in North America....yup.
Do I think Daimler-Chrysler are worried about liability issues in Europe...nope.
Do I think Daimler-Chrysler are worried about liability issues in Europe...nope.
Gee, I wonder why? hmm.. how many lawyers per million do we have, and how many does a typical EU nation have?
You have a few (VERY) isolated instances of failure of this system that are not more, or less frequent than failures of any other brake system is the information that I've been given from a few credible sources... like the DOT (I chatted with an engineer there for about 20 min about the CDI specifically, and SBC in passing), and most of them were on earlier models from 2002/3 and in Europe.
Spartan, I believe you are the only person who had a total failure of this system that I have come across on 4 or 5 different forums on MB (where the loud minority hang out).. and your car was a pre-recall system which was not fixed before the failure, so it's just not fair to pain in this broad brush the entire SBC fleet of E, S and CLS cars.
I flew FBW (Fly-by-wire) jets for 10 years and not once did I worry about a failure just because it was remotely possible... reality is (and SBC is the same) there is redundancy and it's generally statistically impossible to experience a failure on the latest updated system.
IT DOES NOT FAIL UNTIL YOU APPLY THE BRAKES. That means you find out while you are applying the brakes and absolute horror sets in for a half second....then reflexes take over.....and if you are lucky enough to stop safely, the twilight zone of red hot ANGER takes over. THANK GOD I have some racing experience and my reflexes are still quick enough...otherwise...my wife would be doing interviews on DateLine....and enjoying her jury awarded millions. If you haven't felt the "experience", then you can't dismiss it.
Just for fun, next time you drive down the highway and someone stops in front of you, just PRETEND you are applying the brakes and see how it feels to fly without brakes. Or go through a school section while 5 kids stroll across in front of you.
Look, I'm sorry that I have an aggressive tone about this, but it's something that MUST NOT be swept under the carpet or dismissed. The system should have NEVER been developed to be brake-by-wire. All the things the SBC system does can be done through the "old fashion" brake system. After all, they are doing it for the new S class. The consequences of failure are potentially so catastrophic that even 1 in 10,000 is FAR too much. How would you feel if you are the "lucky" one? My contention is that it should not happen to ANYONE.
Bottom line.....
I really like the E-class, so much so that I did not take anything else even when I was given the opportunity and did not want a refund. However, Mercedes has blundered with this system and should have thought of something more fail safe. I am glad that they will remove it from my '09 purchase.
Last edited by Spartan; Aug 6, 2005 at 03:16 AM.
The Best of Mercedes & AMG
Two, so far as I know the failures we've heard about in the U.S. were due to the system erroneously shutting down because it thought it had a problem. In every case it appears that was because of inexperienced service personal failing to complete a bleeding process.
Three, the brake recall DID NOT FIX ANYTHING. All that it did was program a counter of brake applications so that the car operator could be given a notice to take the car in for service before the pump wore out. None of us will keep our cars long enough to ever see that message.
I'm not belittling anyone's experiences with an SBC shutdown because it falsely thought there was a problem. The system shouldn't have shut down in these cases and it would not have if the vehicles had not had an incorrect brake bleeding procedure (incomplete bleeding).
Now that dealers know what they are doing (hopefully), there should not be any more of these isolated incidents.
BTW, as far as I know, Bosch is footing the bills on any failures.
As for the failure mode... that is not the case according to MB, they say that if it fails, it REVERTS to a manual back up which *yes* requires additional pressure and a longer braking distance... so you're must have been a 1 in 1,000,000 situation that was caused by a failed backup system.
In certain aircraft I've flown, if you have a failure of the braking system, you have a similar reversionary mode.. so goes life. But then, do we stop progress? and keep stopping airplanes like we did in the 1940's? or do we move into brake-by-wire?
Anyway, we're going in circles here... I'm happy with SBC.. and I'm sure we'll see more of it in future cars, as the technology is perfected (AND MADE COST EFFECTIVE)
BTW, as far as I know, Bosch is footing the bills on any failures.
I am not minimizing your experience but I am also not buying the idea that anything failed other than the guy who bled your brakes.
The cases in Europe where the pumps wore out were related to vehicles with very high brake applications (taxi's with 300K plus applications). That's why Mercedes have programmed in a counter to remind people to take their cars in for service before the pumps do wear out.
As MB_Jim pointed out, the brakes are being changed on the 2007 E-Class due out late next year. Anyone who cannot trust the SBC system can get an E-Class that apparently uses the master cylinder to provide power for the brakes.
However, it might be a good idea not to be one of the first to get the new brakes just as it wasn't a good idea to buy a 2003 E-Class.
As for the failure mode... that is not the case according to MB, they say that if it fails, it REVERTS to a manual back up which *yes* requires additional pressure and a longer braking distance... so you're must have been a 1 in 1,000,000 situation that was caused by a failed backup system.
In certain aircraft I've flown, if you have a failure of the braking system, you have a similar reversionary mode.. so goes life. But then, do we stop progress? and keep stopping airplanes like we did in the 1940's? or do we move into brake-by-wire?
Anyway, we're going in circles here... I'm happy with SBC.. and I'm sure we'll see more of it in future cars, as the technology is perfected (AND MADE COST EFFECTIVE)
The manual brake sytem is still there but you must push the pedal ALL THE WAY TO THE FLOOR because it only work in the last half inch. On top of that, it takes an enormous effort to stop the car. In fact, you need to use TWO FEET.
Now, let's get serious, how many people are going to think that there is still a system in place if the push on the brake and nothing happens? Worse still, do you think any normal person would think of "compensating" for SBC failure while their life was flashing in front of them? Do Mercedes E-class drivers have to take special courses in case their SBC fails? The theory of their back-up is nice and dandy, but in real life, it does not work.
I also fly but every time I go up, I make a concious decision to take my life into my hands and the increased risk. When one buys a Mercedes, one does NOT expect to be a test pilot for the SBC system failure.
Anywho......
I don't want to go for ever about this......and I really hope everyone follows their brake recall program.
I am not minimizing your experience but I am also not buying the idea that anything failed other than the guy who bled your brakes.
The cases in Europe where the pumps wore out were related to vehicles with very high brake applications (taxi's with 300K plus applications). That's why Mercedes have programmed in a counter to remind people to take their cars in for service before the pumps do wear out.
As MB_Jim pointed out, the brakes are being changed on the 2007 E-Class due out late next year. Anyone who cannot trust the SBC system can get an E-Class that apparently uses the master cylinder to provide power for the brakes.
However, it might be a good idea not to be one of the first to get the new brakes just as it wasn't a good idea to buy a 2003 E-Class.
Again, I love the product. I am a loyal Mercedes customer for decades and I will continue to be a loyal customer.
There is a second recall program that is to ensure that a cable connector does not come loose. So far as I know, MBUSA hasn't even sent out letters about it so it can't be all that crucial.
In other words, the first recall was more for Mercedes benefit than anything else and the second one doesn't appear to be all that critical and is only a preventive process.
One possibility for system redunancy would have Mercedes retaining the vacuum assist as a back-up.
If I remember correctly, it was Fazooley who had his SBC system fail.
With SBC, I would seriously be concerned about the long term reliability of the system. This is something that any of us will not know for a while, but my guess is that MB realizes that over-engineering things like the brakes is not something that should be taken lightly. They are trying to improve their reliability, and I can't see this system being cheap or easy to fix in the future.
All credit to Spartan in getting a second vehicle, but if you have no confidence in it, then go for a different brand.
Is SBC dangerous? Why is it fitted into the SLR?
Have a nice day everyone,
Regards,
John
Finally, Spartan had a very scary experience, yet he got back into an SBC E class, which tell me he knows in his heart, this is not likely to happen again. PLUS, he now knows exactly what to do if it should fail.
MB DEALERS and SALESMAN NEED TO STRESS THE EMERGENCY PROCEDURE ON THE SBC SHOULD IT FAIL TO ALL OF THEIR CUSTOMERS. I CAN TELL YOU THIS, MY WIFE KNOWS!
People freak out during hard braking and that causes accidents? I suppose the average driver is too stupid to know that is what happens when ABS kicks in.
Sam - why do you seem so emotional about SBC? I had it - hated it and voted with my dollars and bought something else. IMO it was just technology for technologies sake.
Not worth the expense, noise penalty, feel penalty, complication and weight IMO.
Last edited by lig; Aug 6, 2005 at 02:02 PM.
Sam - why do you seem so emotional about SBC? I had it - hated it and voted with my dollars and bought something else. IMO it was just technology for technologies sake.
Because I fought the same battle with guys in Aviation that talked a lot of garbage about FBW (and now Engines by wire) as though we should still be flying Wright Radials with A/C electrical across the Atlantic. Technology is good, we should welcome it, not call it a waste of time.
This is why, I get emotional. For me SBC was a selling point.
http://www.whnet.com/4x4/sbc.html
Now.. Read this link on SBC, and especially take note of the advantages during a turn (as displayed in the diagram)
And there there is this telling quote:
Last edited by CE750; Aug 6, 2005 at 10:58 PM.



