R129 Soft Top & ADS - Different Fluids?

[MB-Dude]

Read some information today that implied different hydraulic fluids are used in the R129 Soft Top Hydraulics and the Adaptive Damping System (ADS). I was under the impression from a Mercedes Dealer that MB Hydraulic Fluid (MB p/n: 000.989.91.03.10) was useable in both systems.

Further complicating matters, Mercedes changed part numbers. However, I was told the latest is MB Hydraulic Fluid (MB p/n: 001.989.20.03.10) and still applicable to both systems.

Question: Are two different hydraulic fluids used in the R129 - one for the soft top and one for the ADS? If so, what MB part numbers for hydraulic fluid should I be using in each system?

[iwrock]

Huh?

I was told there are two different fluids by many different sources...

[tecqboy]

What does it say in the owners manual?

[MB-Dude]

The Owner’s Manual is vague on the subject – simply says to use MB Hydraulic Fluid. However, the 2001 Factory Approved Service Products, page 6, provides the following information:

SL-Class
Hydraulic Oil
For load leveling systems, hydropneumatic suspension, hydraulic soft top
MB Hydraulic Oil MB part no. 000 989 91 03 10

Although the .pdf size is only 289K, file size restrictions of this site prevent me from uploading the document. So you’ll have to take my word for it. But clearly in 2001, MB documents that the R129 model uses one fluid for both ADS (load leveling systems, hydropneumatic suspension) and soft top mechanism.

However, newer vehicles seem to have a reference for two different fluids, as found in the Factory Approved Service Products September 2006 document. Again, file restrictions do not allow me to upload this document either, but I believe it is readily available.

For hydraulic soft top, retractable hardtop
MB Hydraulic Oil - MB Part No. A000 989 91 03 10

Active Body Control Fluid
MB ABC Fluid - MB Part No. BQ 1 32 0001

Now it is possible that MB ABC Fluid (MB p/n: BQ.1.32.0001) is usable in the R129 ADS, and if so, I’m only looking for confirmation/experience from others. It would also be good to know why the ABC Fluid is considered a better alternative to the traditional MB Hydraulic Fluid.

The R129 model had long ceased production in 2006 and I think this is where the confusion lies - newer models require 2 fluids; older ones only need one... or so the documentation implies. But now you see why I asked the question - at least up to 2001, there seemed to be only one hydraulic fluid for the R129.

[lynns]

Please read M-B Approved Service Products for the answer to your question.

[MB-Dude]

Originally Posted by lynns

Please read M-B Approved Service Products for the answer to your question.

Thanks for the link as that is the same document I referenced in my post #4 above. In 2001, the recommendation was one fluid for both ADS and Soft Top hydraulics - MB Hydraulic Oil part no. 000 989 91 03 10.

But some folks are under the impression two fluids are required in the R129 model. So the follow-on question was: Is there an advantage to following the MB recommendations from the 2006 Factory Approved Service Products document, which outlines one fluid for ABC and a different fluid for Soft Top hydraulics?

It's possible advances have been made in the specification of MB hydraulic fluids that might mean MB ABC Fluid (p/n: BQ 1 32 0001) is now considered better for suspensions.

[lynns]

Originally Posted by MB-Dude

Question: Are two different hydraulic fluids used in the R129 - one for the soft top and one for the ADS? If so, what MB part numbers for hydraulic fluid should I be using in each system?

This a question for R129 SL600 owners or a very rare SL500 owner with the ADS option.

[MB-Dude]

Originally Posted by lynns

This a question for R129 SL600 owners or a very rare SL500 owner with the ADS option.

Specifically in my case, I have ADS in the '96 SL600; no ADS in my '94 SL500. Are the ADS systems different between the R129 V12 and V8 models?

[lynns]

Originally Posted by MB-Dude

Specifically in my case, I have ADS in the '96 SL600; no ADS in my '94 SL500. Are the ADS systems different between the R129 V12 and V8 models?

NO! Please see http://www.benzworld.org/forums/r129-sl-class/1317915-2002-sl500-ads-option.html?highlight=ads