The ABC Suspension Thread
Junior Member
Joined: Jan 2015
Posts: 20
Likes: 2
mercedes 190 Mercedes 600 sel Audi A8
How does the ABC sport setting work
hello
i have read a lot in this thread and maybe it is already explained but i have not seen it
in ABC sport is sets the car more firm on the road and the suspension is much harder
so as i think it should work is normally i will use the accumulator to get a sort of spring rate
but how does is it firm up this ?
it can not just shut the valve like in of position and it does not feel like that
if there is build up more pressure in the system it normally just raise the car up because the strut is a 1 way route
where the oil is going in
maybe somebody can explain how the oil system works in sport mode how does it keep the car comfortable and sporty in ABC sport?
Thanks
Very nice thread to read
i have read a lot in this thread and maybe it is already explained but i have not seen it
in ABC sport is sets the car more firm on the road and the suspension is much harder
so as i think it should work is normally i will use the accumulator to get a sort of spring rate
but how does is it firm up this ?
it can not just shut the valve like in of position and it does not feel like that
if there is build up more pressure in the system it normally just raise the car up because the strut is a 1 way route
where the oil is going in
maybe somebody can explain how the oil system works in sport mode how does it keep the car comfortable and sporty in ABC sport?
Thanks
Very nice thread to read
Junior Member
Joined: Jan 2019
Posts: 22
Likes: 8
From: St. Louis, MO
ML350, W221 S65
S65 ABC Flush Just Completed
Not sure if this is the right spot to post this, but I made a video of the ABC flush that I just did in my new (to me) 2012 S65. The car has 30k miles at the time of this flush. I used the AGA tool to make it easier. I purchased 11 liters of Pentosin at the local dealer ($30/liter) and a new filter. It all went pretty smoothly, but I was nervous as I had never done this before, only read about it on this and other forums.
I hope this video is helpful to those who have not done a flush before.
I'd love to hear feedback.
Thanks.
John
I hope this video is helpful to those who have not done a flush before.
I'd love to hear feedback.
Thanks.
John
Not sure if this is the right spot to post this, but I made a video of the ABC flush that I just did in my new (to me) 2012 S65. The car has 30k miles at the time of this flush. I used the AGA tool to make it easier. I purchased 11 liters of Pentosin at the local dealer ($30/liter) and a new filter. It all went pretty smoothly, but I was nervous as I had never done this before, only read about it on this and other forums.
I hope this video is helpful to those who have not done a flush before.
https://www.youtube.com/watch?v=PC1vDOcw54M
I'd love to hear feedback.
Thanks.
John
I hope this video is helpful to those who have not done a flush before.
https://www.youtube.com/watch?v=PC1vDOcw54M
I'd love to hear feedback.
Thanks.
John
Thread Starter
MBWorld Fanatic!
Joined: Nov 2010
Posts: 2,605
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From: Welwyn, Herts, UK
2006 S600
Can you elaborate a bit more on what problems you used to have, exactly what work was performed, and by who, and when, what happened after the work was completed, was the pump primed, and are there any other symptoms, such as warning lights or an overflowing reservoir? ?
Nick
Nick
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W221 S500mco Mercedes 2008
Abc
u might be the only that can help me with this problem the abc pump started leaking oil by the time it came up on dash and I noticed fresh pump oil on my driveway the suspension went hard but when topped it up with the correct oil it came back to normal unfortunately the 2nd time I filled it it stayed hard ever since it’s had numerous rodeos and other tests but no fault found no other lights on dash and no faults found still break your teeth on bumpy rd all this after several inependent garages and Mercedes’s themselves looked at it all back sensors replaced sure hope u can shed light on it
Newbie
Joined: Sep 2019
Posts: 10
Likes: 1
W221 S500mco Mercedes 2008
Abc
nick could u suggest what might be the cause of hard suspension on w221 S500mco Mercedes it was really smooth until a leak from abc pump fluid ran too low and suspension went hard replaced with new Mercedes abc pump but suspension stayed I’ve had numerous rodeo tests and replacement sensors but no change sometimes suspension is raised at front driver side wheel and lower at rear passenger side I’ve almost given up on resolving this problem
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
Nick
Thank you for taking so much time to document everything like you have. I have an SL65 and have weeping from a couple of lines that disappear up into the engine bay right in front of the engine. I am guessing that these lines go to the hydraulic pump, is that right? I have tried to scour the WIS and EPC but cannot clearly narrow down which one it is ... it disappears into a very tight space somewhere between the reservoir and the pump. Many of the pics in this thread unfortunately appear to be broken (at least I can't see them) and those I can see don't appear to match those on my car.
The hoses forward of those appear to be bone dry .. they go from the front valve block to each side, so I don't think I'll touch those for now since they are dry.
Would appreciate any help here.
Cheers
Thank you for taking so much time to document everything like you have. I have an SL65 and have weeping from a couple of lines that disappear up into the engine bay right in front of the engine. I am guessing that these lines go to the hydraulic pump, is that right? I have tried to scour the WIS and EPC but cannot clearly narrow down which one it is ... it disappears into a very tight space somewhere between the reservoir and the pump. Many of the pics in this thread unfortunately appear to be broken (at least I can't see them) and those I can see don't appear to match those on my car.
The hoses forward of those appear to be bone dry .. they go from the front valve block to each side, so I don't think I'll touch those for now since they are dry.
Would appreciate any help here.
Cheers
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
Hi all I managed to remove the connection pipe from the tandem pump. The banjo bolt on it was super tight. There is a double banjo that goes into the pump. I had to use a long breaker bar and 1/2" extensions that could poke through a plastic cover from the front control arm to break it loose. It was definitely not designed for serviceability.
I took the hose to a local shop and they said they could not compression fit onto the banjo side as there was not enough length of pipe. I took it to another place to see if they could braze a solid pipe on and then I could fit the hose. The guy pointed out that I have some additional crimps on the pipe (in red) Does anyone know what these crimps are? The guy mentioned that they could be restrictors but I have no idea. Would it be bad to just put a hose there? I don't mind getting a new hose, but I thought I'd save some $$ and then also could select higher grade hydraulic hose.
Thanks
I took the hose to a local shop and they said they could not compression fit onto the banjo side as there was not enough length of pipe. I took it to another place to see if they could braze a solid pipe on and then I could fit the hose. The guy pointed out that I have some additional crimps on the pipe (in red) Does anyone know what these crimps are? The guy mentioned that they could be restrictors but I have no idea. Would it be bad to just put a hose there? I don't mind getting a new hose, but I thought I'd save some $$ and then also could select higher grade hydraulic hose.
Thanks
Last edited by turbo97se; Oct 18, 2019 at 07:32 PM.
Thread Starter
MBWorld Fanatic!
Joined: Nov 2010
Posts: 2,605
Likes: 343
From: Welwyn, Herts, UK
2006 S600
hello
i have read a lot in this thread and maybe it is already explained but i have not seen it
in ABC sport is sets the car more firm on the road and the suspension is much harder
so as i think it should work is normally i will use the accumulator to get a sort of spring rate
but how does is it firm up this ?
it can not just shut the valve like in of position and it does not feel like that
if there is build up more pressure in the system it normally just raise the car up because the strut is a 1 way route
where the oil is going in
maybe somebody can explain how the oil system works in sport mode how does it keep the car comfortable and sporty in ABC sport?
Thanks
Very nice thread to read
i have read a lot in this thread and maybe it is already explained but i have not seen it
in ABC sport is sets the car more firm on the road and the suspension is much harder
so as i think it should work is normally i will use the accumulator to get a sort of spring rate
but how does is it firm up this ?
it can not just shut the valve like in of position and it does not feel like that
if there is build up more pressure in the system it normally just raise the car up because the strut is a 1 way route
where the oil is going in
maybe somebody can explain how the oil system works in sport mode how does it keep the car comfortable and sporty in ABC sport?
Thanks
Very nice thread to read
Firstly, the dampers are set to firm. There is an electrical control that goes into the top of the strut. This is nothing to do with the hydraulics.
Secondly, the roll control compensation is increased in sport mode, so that body roll is reduced.
Regards,
Nick
Thread Starter
MBWorld Fanatic!
Joined: Nov 2010
Posts: 2,605
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From: Welwyn, Herts, UK
2006 S600
u might be the only that can help me with this problem the abc pump started leaking oil by the time it came up on dash and I noticed fresh pump oil on my driveway the suspension went hard but when topped it up with the correct oil it came back to normal unfortunately the 2nd time I filled it it stayed hard ever since it’s had numerous rodeos and other tests but no fault found no other lights on dash and no faults found still break your teeth on bumpy rd all this after several inependent garages and Mercedes’s themselves looked at it all back sensors replaced sure hope u can shed light on it
Thing is, the conventional springs and dampers are still there even when something goes wrong with ABC. The usual fault symptom is the "tuna boat" ride - it gets bouncy and wallowing and rolls, but it doesn't get harsh.
I can't explain your observations very well. The best I can suggest is to replace the accumulators, and change the suspension oil and filter.
If that doesn't help, take a very close look at the suspension level control linkages. They're prone to seizing, and in the short term that can degrade the ride.
Nick
Thread Starter
MBWorld Fanatic!
Joined: Nov 2010
Posts: 2,605
Likes: 343
From: Welwyn, Herts, UK
2006 S600
Hi all I managed to remove the connection pipe from the tandem pump. The banjo bolt on it was super tight. There is a double banjo that goes into the pump. I had to use a long breaker bar and 1/2" extensions that could poke through a plastic cover from the front control arm to break it loose. It was definitely not designed for serviceability.
I took the hose to a local shop and they said they could not compression fit onto the banjo side as there was not enough length of pipe. I took it to another place to see if they could braze a solid pipe on and then I could fit the hose. The guy pointed out that I have some additional crimps on the pipe (in red) Does anyone know what these crimps are? The guy mentioned that they could be restrictors but I have no idea. Would it be bad to just put a hose there? I don't mind getting a new hose, but I thought I'd save some $$ and then also could select higher grade hydraulic hose.
Thanks
I took the hose to a local shop and they said they could not compression fit onto the banjo side as there was not enough length of pipe. I took it to another place to see if they could braze a solid pipe on and then I could fit the hose. The guy pointed out that I have some additional crimps on the pipe (in red) Does anyone know what these crimps are? The guy mentioned that they could be restrictors but I have no idea. Would it be bad to just put a hose there? I don't mind getting a new hose, but I thought I'd save some $$ and then also could select higher grade hydraulic hose.
Thanks
The high pressure fluid that comes out of the pump has a relatively low flow rate, and I don't think it needs restricting (as if that would do any good). The banjo itself acts as a restrictor to some extent, but in any case the hose feeds the pressure control valve and accumulator, and they do the hydraulics conditioning.
If you don't have room to connect a compression fitting, try cutting off the crimp and using the pipe inside, like this
:
Nick
Last edited by Welwynnick; Oct 19, 2019 at 05:26 AM.
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
Nick
Thank you for the picture and sharing your thoughts here. I took more pictures to share:
Below, I dremeled (made 4 cuts) through the crimp. There are ribs that compress the hose even more. Once you cut through those, then stop cutting. I then used a screw driver and pliers to break them off at the end. I was doing this carefully as I have not done this before.
Below is what the whole hose looks like when cut apart. I am going to ask the shop to put a line in the same length as this line. After that, I am going to cut this one open and see what those additional crimps are actually doing. There is an outer rubber "jacket" on the hose ... I think one of them is just preventing the outer jacket from moving.
Below is a close up of the banjo fitting:
I have cleaned up the fittings and bagged them ready for a new hose.
Also as I mentioned earlier, I found an easy path to get to the tandem pump banjo bolt. Removing the front control arm bolt and pushing past the plastic dustcover gives a straight shot up to the banjo bolt. This was on R230 SL65, not sure if other V12s have this, but thought it might help someone.
Cheers everyone!
Thank you for the picture and sharing your thoughts here. I took more pictures to share:
Below, I dremeled (made 4 cuts) through the crimp. There are ribs that compress the hose even more. Once you cut through those, then stop cutting. I then used a screw driver and pliers to break them off at the end. I was doing this carefully as I have not done this before.
Below is what the whole hose looks like when cut apart. I am going to ask the shop to put a line in the same length as this line. After that, I am going to cut this one open and see what those additional crimps are actually doing. There is an outer rubber "jacket" on the hose ... I think one of them is just preventing the outer jacket from moving.
Below is a close up of the banjo fitting:
I have cleaned up the fittings and bagged them ready for a new hose.
Also as I mentioned earlier, I found an easy path to get to the tandem pump banjo bolt. Removing the front control arm bolt and pushing past the plastic dustcover gives a straight shot up to the banjo bolt. This was on R230 SL65, not sure if other V12s have this, but thought it might help someone.
Cheers everyone!
Last edited by turbo97se; Oct 19, 2019 at 03:24 PM.
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
Well it looks like my local hydraulic place said these are custom fittings (hose barb fittings) and not able to do it. I thought it would be fairly straight forward but I guess not ... May need to cut the solid pipe and braze on compression fittings. It's starting to get messy again.
Newbie
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SL65amg
Well it looks like my local hydraulic place said these are custom fittings (hose barb fittings) and not able to do it. I thought it would be fairly straight forward but I guess not ... May need to cut the solid pipe and braze on compression fittings. It's starting to get messy again.
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
I forgot to post back what happened in the end. Well after cutting the second pipe open, I found there was a plastic tube connected to the banjo side that ran down the centre of the hydraulic line. It is possibly a restrictor of some kind. The other pipe could have been easily fixed but the place where I took the parts to be welded wanted stupid money for welding the fittings on. With that and the plastic pipe, I just didn't want to mess with it and bought a new set
The new lines come as a pair and even a new bolt which is a bonus. I almost bought the bolt separately but at about $115 for that banjo bolt, I thought I would re-use mine. It came with one so I used the new one.
I wasn't doing this just purely to save money, although it was a good part of the motivation for going through this. Was hoping to put in stronger lines to minimize the chance of it blowing in the future. If you can find the ferrules for the ends, you can just put in new hydraulic lines and crimp them to the old fittings. I contacted quite a few hydraulic shops but none had the ferrules for it. I guess it may be more common in Europe than in the US. Good luck!
The new lines come as a pair and even a new bolt which is a bonus. I almost bought the bolt separately but at about $115 for that banjo bolt, I thought I would re-use mine. It came with one so I used the new one.
I wasn't doing this just purely to save money, although it was a good part of the motivation for going through this. Was hoping to put in stronger lines to minimize the chance of it blowing in the future. If you can find the ferrules for the ends, you can just put in new hydraulic lines and crimp them to the old fittings. I contacted quite a few hydraulic shops but none had the ferrules for it. I guess it may be more common in Europe than in the US. Good luck!
Last edited by turbo97se; Apr 20, 2020 at 03:32 PM.
Newbie
Joined: Apr 2020
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SL65amg
I forgot to post back what happened in the end. Well after cutting the second pipe open, I found there was a plastic tube connected to the banjo side that ran down the centre of the hydraulic line. It is possibly a restrictor of some kind. The other pipe could have been easily fixed but the place where I took the parts to be welded wanted stupid money for welding the fittings on. With that and the plastic pipe, I just didn't want to mess with it and bought a new set
The new lines come as a pair and even a new bolt which is a bonus. I almost bought the bolt separately but at about $115 for that banjo bolt, I thought I would re-use mine. It came with one so I used the new one.
I wasn't doing this just purely to save money, although it was a good part of the motivation for going through this. Was hoping to put in stronger lines to minimize the chance of it blowing in the future. If you can find the ferrules for the ends, you can just put in new hydraulic lines and crimp them to the old fittings. I contacted quite a few hydraulic shops but none had the ferrules for it. I guess it may be more common in Europe than in the US. Good luck!
The new lines come as a pair and even a new bolt which is a bonus. I almost bought the bolt separately but at about $115 for that banjo bolt, I thought I would re-use mine. It came with one so I used the new one.
I wasn't doing this just purely to save money, although it was a good part of the motivation for going through this. Was hoping to put in stronger lines to minimize the chance of it blowing in the future. If you can find the ferrules for the ends, you can just put in new hydraulic lines and crimp them to the old fittings. I contacted quite a few hydraulic shops but none had the ferrules for it. I guess it may be more common in Europe than in the US. Good luck!
Where did you get the hose assemblies, and what are the p/n's for them? I have a hard time locating them online.
Last question, did you manage to replace the hose assemblies without lifting the engine? TKS!!
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
I can give you the part number I used. It was 2303209353. if you want me to confirm the part number, you can PM me your VIN and I will look it up for you to confirm. My buddy got it for me since he has some connections and owed me a favor. I would recommend you check on-line Mercedes parts retailers as I don't think he got the best price.
These particular hoses did not need the engine to be lifted. The key for me was finding the access to the banjo bolt through the front control arm mount. There is no way I could have loosened that banjo from other angles. Don't know how others managed it.
These particular hoses did not need the engine to be lifted. The key for me was finding the access to the banjo bolt through the front control arm mount. There is no way I could have loosened that banjo from other angles. Don't know how others managed it.
Thank you very much for taking time to respond, highly appreciated!
Where did you get the hose assemblies, and what are the p/n's for them? I have a hard time locating them online.
Last question, did you manage to replace the hose assemblies without lifting the engine? TKS!!
Where did you get the hose assemblies, and what are the p/n's for them? I have a hard time locating them online.
Last question, did you manage to replace the hose assemblies without lifting the engine? TKS!!
Newbie
Joined: Apr 2020
Posts: 11
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SL65amg
I can give you the part number I used. It was 2303209353. if you want me to confirm the part number, you can PM me your VIN and I will look it up for you to confirm. My buddy got it for me since he has some connections and owed me a favor. I would recommend you check on-line Mercedes parts retailers as I don't think he got the best price.
These particular hoses did not need the engine to be lifted. The key for me was finding the access to the banjo bolt through the front control arm mount. There is no way I could have loosened that banjo from other angles. Don't know how others managed it.
These particular hoses did not need the engine to be lifted. The key for me was finding the access to the banjo bolt through the front control arm mount. There is no way I could have loosened that banjo from other angles. Don't know how others managed it.
Looking closer at the hose assembly it seems like the leakage is coming from the hose that ends with a dead pipe. Right after the extra rubber sleeve (on the banjo side of the assembly) there is some kind of restrictor or similar (like a metal waist on the cable). On the rubber sleeve side of the “waist” the hose is wet (can see it only if I lift up the rubber sleeve somewhat and peek underneath). Do you know what these “waists” are? Seems strange to have them in the middle of the hose. Is there a connection or joint inside these “waists”? Is it possible to have a leak from there?
Very hard so see the bajo bolt from under the car, but I get your point in removing the control arm and access behind the plastic cover. Damn tight though!
THANKS!
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
Replied to your PM, the part number is the same as mine (if yours is leaking in the same location). One thing that might be worth trying is to wipe those joints off and see if it still leaks. One other possible place it could leak is from the banjo area and could be the seals at the banjo dripping down to the joints. The joints themselves I do not know why they are there and asked a more knowledgable person about it and they could not guess either. The crimps on the other hose could be to hold the plastic piping in place, but this one I don't know.
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2005 S500 Designo
2005 S55 here. Getting intermittent Red warnings on the dash, Take to Shop, Drive Carefully.
But I looked under the hood and the ABC dipstick cap was loose. Could that cause those error messages? Does the system need to be sealed tightly?
Because it was completely loose and once I pushed it on properly and drove the car, I had no more Red messages.
But I looked under the hood and the ABC dipstick cap was loose. Could that cause those error messages? Does the system need to be sealed tightly?
Because it was completely loose and once I pushed it on properly and drove the car, I had no more Red messages.
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2001 CL500
Man I’d love to talk to you. I have a 03 CL600 & the front line just sprouted a hole.
Mercedes’s wants $3,300 to do it. I can do it but I just don’t have anywhere to tackle a job like that. Everyone’s sayin to just put coil overs on it but I’m not sure I wanna get rid of the ABC
INTRODUCTION
Mercedes is a great innovator, and one of their great achievements IMHO is Active Body Control suspension, where engine power is used to actively and dynamically compensate for body motion due to acceleration, braking and especially cornering. There is virtually no pitch and roll, no-matter how hard you throw the car around, but it does this with soft springs and great ride comfort.
However, its also a great liability due to its complexity and novelty. ABC had been developed over a period of decades, was introduced in the W215 CL-class coupe in 1998, and the W220 shortly after that. Owners of those cars in particular became guinea pigs due to the immaturity of the implementation. Springs and dampers have been developed over a very long period of time, but the mixture of hydraulics and electronics had not. At least not in an automotive environment.
I've owned four W220's with ABC, but only one has given me any problems, and the intensive practical experience of finding solutions is the starting point for this thread.
I'm not going to attempt to write the book on ABC - I have to spend my free time working on my car, and in any case the book has already been written by Daren B:
http://mercedes-abc-drive-carefully.blogspot.co.uk/
If you've had a problem with ABC, you've probably read that already, and its definitely the place to start. I think many MB dealers and specialist garages could do much worse than to study that blog. The other superb DIY maintenance thread is by Howard, and many of you will have seen this as well. Both are compulsory reading for ABC:
https://mbworld.org/forums/s-class-w...2003-s600.html
This thread is quite a long-standing ambition for me, as ABC is such a great stumbling block for so many owners. It can make you lose confidence in your ability to drive from A to B, and make it financially unviable to keep a perfectly good car on the road. Over the last three years I found a lot of practical and economical solutions to ABC problems, and I want to share them and discuss them.
Why this forum? It's kind of home for me in some ways, being the owner of two V12s, but the cars that use the V12 engine are also the cars that use ABC. Its a pretty quiet technical forum, and I wanted a bit time to put this together before it got noisy. ABC is used on S-class, SL-class and CL-class cars, across two or three generations of those cars, and across Mercedes and AMG models in each case. So there are lots of permutations of models, each with their own forum, where ABC is a significant point of discussion. There are over 1000 threads about ABC, and they're pretty evenly distributed over the various forums. If a moderator wanted to put this somewhere else more appropriate, that would fine.
Nick
Mercedes is a great innovator, and one of their great achievements IMHO is Active Body Control suspension, where engine power is used to actively and dynamically compensate for body motion due to acceleration, braking and especially cornering. There is virtually no pitch and roll, no-matter how hard you throw the car around, but it does this with soft springs and great ride comfort.
However, its also a great liability due to its complexity and novelty. ABC had been developed over a period of decades, was introduced in the W215 CL-class coupe in 1998, and the W220 shortly after that. Owners of those cars in particular became guinea pigs due to the immaturity of the implementation. Springs and dampers have been developed over a very long period of time, but the mixture of hydraulics and electronics had not. At least not in an automotive environment.
I've owned four W220's with ABC, but only one has given me any problems, and the intensive practical experience of finding solutions is the starting point for this thread.
I'm not going to attempt to write the book on ABC - I have to spend my free time working on my car, and in any case the book has already been written by Daren B:
http://mercedes-abc-drive-carefully.blogspot.co.uk/
If you've had a problem with ABC, you've probably read that already, and its definitely the place to start. I think many MB dealers and specialist garages could do much worse than to study that blog. The other superb DIY maintenance thread is by Howard, and many of you will have seen this as well. Both are compulsory reading for ABC:
https://mbworld.org/forums/s-class-w...2003-s600.html
This thread is quite a long-standing ambition for me, as ABC is such a great stumbling block for so many owners. It can make you lose confidence in your ability to drive from A to B, and make it financially unviable to keep a perfectly good car on the road. Over the last three years I found a lot of practical and economical solutions to ABC problems, and I want to share them and discuss them.
Why this forum? It's kind of home for me in some ways, being the owner of two V12s, but the cars that use the V12 engine are also the cars that use ABC. Its a pretty quiet technical forum, and I wanted a bit time to put this together before it got noisy. ABC is used on S-class, SL-class and CL-class cars, across two or three generations of those cars, and across Mercedes and AMG models in each case. So there are lots of permutations of models, each with their own forum, where ABC is a significant point of discussion. There are over 1000 threads about ABC, and they're pretty evenly distributed over the various forums. If a moderator wanted to put this somewhere else more appropriate, that would fine.
Nick
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2004 CL 500, 2013 Porsche Cayenne
ABC a few questions
Cl 500 139,000.
i was changing the accumulators yesterday 3 of 4.
Front main and return we’re almost to simple.
Muffler bolts were rusted -snapped also the bracket that the bolts go through was half was already broken in 2 pieces. Any one have a part number?
After the muffler was out, the line going to the accumulator was also frozen and I felt if I put anymore pressure I would have broken the line. I also need the part number for that line? Does anyone have a full set of hoses off the car for sale?
While I was struggling with a the rear accumulator I noticed the rear strut has a small leak. I have been watching the abc fluid religiously since I purchased the car last month. Anyone have any idea who long I long the clock is in the repair. Also should they be changed in pairs.
Thank you in advance.
Jim
i was changing the accumulators yesterday 3 of 4.
Front main and return we’re almost to simple.
Muffler bolts were rusted -snapped also the bracket that the bolts go through was half was already broken in 2 pieces. Any one have a part number?
After the muffler was out, the line going to the accumulator was also frozen and I felt if I put anymore pressure I would have broken the line. I also need the part number for that line? Does anyone have a full set of hoses off the car for sale?
While I was struggling with a the rear accumulator I noticed the rear strut has a small leak. I have been watching the abc fluid religiously since I purchased the car last month. Anyone have any idea who long I long the clock is in the repair. Also should they be changed in pairs.
Thank you in advance.
Jim
MBWorld Fanatic!
Joined: Dec 2005
Posts: 4,057
Likes: 341
From: NJ
2009 SL63 AMG
Nick, first of all, this is an exceptional thread. Thank you for aggregating all of this great info. Bravo sir, truly.
A clarifying question as I am researching wheel/tire options for my '05 S55:
-Are the 18" wheels you are referring to in the 265/40/18 and 275/40/18 configurations the OE wheels for the W220 (in a 4 "rears" square setup) or do we need a different offset from another model to clear the fronts?
Here's the interesting bit, though. I'm interested in the dynamics, and 265/40/18x9 grips and steers better than 245/40/19x8.5 at the front. 275/35/19 at the front are even better, but at the rear they add NOTHING except looks. They add nothing to grip, nothing to ride, nothing to noise, nothing to traction and nothing to steering.
So I think having 265-40-18 all round would be better than staggered 19's, in every respect except maybe looks. Take another look at post 4, picture 3 - the wide rear wheels fill the front arches well, even though they're "only" 9x18's. If you can run 4x18x9 (or 9.5), then 275-40's would probably be a good choice dynamically and aesthetically. Therefore:
4 x 275/40/18x9 is a good conservative choice - better than staggered 19's.
4 x 275/35/19x9.5 is a good ambitious choice - almost certainly better than staggered 20's.
4 x 275/30/20x10 may well work, but its starting to look a bit extreme to me. Bragging rights only, I suspect, and nothing wrong with that.
The S600 isn't the ultimate luxury car, nor the ultimate sports saloon, but with the V12TT and ABC suspension, it gets unbeatably close to being both. So I think an iron fist in a velvet glove is it's raison d'etre - the best compromise between the two. I never realised how close it got until I replaced my pulsation damper this week, and upgrading the front wheels showed a little bit more of what ABC can do. With conventional passive suspension, the wider the tire and the lower the profile - the more the need to minimise camber angle change - paradoxical given the increased body roll.
So bigger tires give diminishing returns - the more grip you provide, the less potential you can realise. Since ABC minimises dynamic camber change, it makes the most of all tyres - but especially wide tyres. Therefore I think an ABC car with say 4 x 275/40/18x9's may give better handling AND ride than ANY Airmatic car with ANY tires, or ANY ABC car with staggered tires. Get greedy with the wheel size though - the brilliant compromise shifts too far, and that iron fist no longer wears a velvet glove.
Nick
So I think having 265-40-18 all round would be better than staggered 19's, in every respect except maybe looks. Take another look at post 4, picture 3 - the wide rear wheels fill the front arches well, even though they're "only" 9x18's. If you can run 4x18x9 (or 9.5), then 275-40's would probably be a good choice dynamically and aesthetically. Therefore:
4 x 275/40/18x9 is a good conservative choice - better than staggered 19's.
4 x 275/35/19x9.5 is a good ambitious choice - almost certainly better than staggered 20's.
4 x 275/30/20x10 may well work, but its starting to look a bit extreme to me. Bragging rights only, I suspect, and nothing wrong with that.
The S600 isn't the ultimate luxury car, nor the ultimate sports saloon, but with the V12TT and ABC suspension, it gets unbeatably close to being both. So I think an iron fist in a velvet glove is it's raison d'etre - the best compromise between the two. I never realised how close it got until I replaced my pulsation damper this week, and upgrading the front wheels showed a little bit more of what ABC can do. With conventional passive suspension, the wider the tire and the lower the profile - the more the need to minimise camber angle change - paradoxical given the increased body roll.
So bigger tires give diminishing returns - the more grip you provide, the less potential you can realise. Since ABC minimises dynamic camber change, it makes the most of all tyres - but especially wide tyres. Therefore I think an ABC car with say 4 x 275/40/18x9's may give better handling AND ride than ANY Airmatic car with ANY tires, or ANY ABC car with staggered tires. Get greedy with the wheel size though - the brilliant compromise shifts too far, and that iron fist no longer wears a velvet glove.
Nick
-Are the 18" wheels you are referring to in the 265/40/18 and 275/40/18 configurations the OE wheels for the W220 (in a 4 "rears" square setup) or do we need a different offset from another model to clear the fronts?
