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Discussion Starter #1 (Edited)
After reading a few threads on here about how difficult the left side accumulator would be to replace, I decided to do the easier side first (right). Doing the right side was a real breeze. I had familiarized myself of where all the bolts where, and what size they were. I also had imagined the muffler being in the way. So, when it came to the real deal, I'd be prepared.

I felt that the writeups on here are great, it was an unmeasurable amount of help. But I also felt that the picture department was a bit lacking, and there's where I wanted to help.

This is for the LEFT side.























About an hour into it.


This bolt was most difficult guy to install. But take a step back and breathe, then retackle.
The hydraulic line is in the way, as well as the muffler. I used a 10mm medium dept socket + a 3" extension to get it started. Then I switched to a 8" extension to finish it off.


Tools used. Snap On, Husky, Duralast, Pittsburg. I am not brand loyal when it comes to tools.



Driving impressions. It seems to bit more "comfortable", but I have not driven it enough to confirm. When I removed the accumulator I did notice that not much fluid came out compared to the right side. I'll be replacing several oil seals when the parts arrive, and at that time I'll be sending the SLSs to Nagengast.



For some reason, I did not have to add any extra Pentosin to the reservoir, any idea why?
 

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looks like a california car! Lack of rust makes these jobs so much easier.

Have you rechecked the sls reservoir level? It should have dropped a bit, for the fluid to fill the new spheres.
 

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Discussion Starter #3
looks like a california car! Lack of rust makes these jobs so much easier.

Have you rechecked the sls reservoir level? It should have dropped a bit, for the fluid to fill the new spheres.

Yes, It's been in the Bay Area all its life! This car has almost 260,00 on it!

As far as the fluid, yes I have checked it. But doesn't seem like it's budging. I try to keep the fluid right at about the mesh level so I can see if it has moved or not.
 

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we've got enough locals to set up a mini meet for coffee or lunch sometime.
 

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....
When I removed the accumulator I did notice that not much fluid came out compared to the right side. ...

For some reason, I did not have to add any extra Pentosin to the reservoir, any idea why?
The accumulator are piped in parallel so both accumulator drain when the line is opened on either side.

Nothing magic about the SLS system, so you should need to add Pentosin as the new accumulators need to be charged for the minimum load and depending how much oil was drained from the shocks (shocks don't drain much if the shock is not moved).
I anticipate if you recheck the reservoir it will be low from filling the accumulators.
Also, Pentosin 7.1 is No Longer Available and if you search the message board you will find a substitute fluid. I will be draining my system of the 7.1 (7.1 cannot be mixed with 11s) and refill it with 11s (synthetic fluid) as I have 2 other BMW that use 11s and that is a good option for me.

Also, It is always a good idea to disconnect the swaybar link (ball joint) to raise and lower the rear suspension to make sure the control valve is working. With the link disconnected, you can also check the minimum ride height and check the SLS ride height setting (adjustment procedure in the repair manual).

Another Bay Area M5 owner...
 

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Also, Pentosin 7.1 is No Longer Available and if you search the message board you will find a substitute fluid. I will be draining my system of the 7.1 (7.1 cannot be mixed with 11s) and refill it with 11s (synthetic fluid) as I have 2 other BMW that use 11s and that is a good option for me.
Febi M6162 is substitube for pentosin 7.1 and can be mixed.
 

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Discussion Starter #9
The accumulator are piped in parallel so both accumulator drain when the line is opened on either side.

Nothing magic about the SLS system, so you should need to add Pentosin as the new accumulators need to be charged for the minimum load and depending how much oil was drained from the shocks (shocks don't drain much if the shock is not moved).
I anticipate if you recheck the reservoir it will be low from filling the accumulators.
Also, Pentosin 7.1 is No Longer Available and if you search the message board you will find a substitute fluid. I will be draining my system of the 7.1 (7.1 cannot be mixed with 11s) and refill it with 11s (synthetic fluid) as I have 2 other BMW that use 11s and that is a good option for me.

Also, It is always a good idea to disconnect the swaybar link (ball joint) to raise and lower the rear suspension to make sure the control valve is working. With the link disconnected, you can also check the minimum ride height and check the SLS ride height setting (adjustment procedure in the repair manual).

Another Bay Area M5 owner...
Thank you for the control valve tip! I will try that later today.

Febi M6162 is substitube for pentosin 7.1 and can be mixed.
Eero is correct. The best place to purchase such fluid is from Pelican Parts. Locally it was $18+tax. From Pelican, it's $10.25 WITH free shipping. Amazing price!

1993 BMW M5 Base Sedan - Steering System - Page 1
 

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Also, Pentosin 7.1 is No Longer Available and if you search the message board you will find a substitute fluid. I will be draining my system of the 7.1 (7.1 cannot be mixed with 11s) and refill it with 11s (synthetic fluid) as I have 2 other BMW that use 11s and that is a good option for me.
What's the best way to flush the system?
 

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For my non m5 touring, the level height adjuster on the left hand side / muffler side has a bleed nipple on the end so I presume you bleed it like brake callipers using the nipple on the level adjuster?
 

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What's the best way to flush the system?
The M5's SLS holds 2.7 liters of Pentosin and given the cost it is not an inexpensive proposal to convert to 11s.
I anticipate it will require at least 4 liters of Pentosin 11s to do the initial system conversion.

I don't think the PS/SLS system using Pentosin 7.1 needs to be drain 100% to convert to 11s.
I would do as complete a drain as possible and flush the PS system and SLS lines with Pentosin 11s before I did a refill with 11s and return the M5 into service with 11s.

With the engine off,
Drain the Pentosin 7.1 from the system:
1) Disconnect the small line flare fitting at the accumulators (Careful because of pressure at SLS system), bounce the rear of the car until all the fluid is discharged (the shocks/accumulators are a blind system and do not circulate Pentosin back to the pump. Bouncing the rear helps get the residual Pentosin out of the shocks). Keep the drain pan in place for flushing Pentosin 11s through the SLS lines (slipping a hose over the flare fitting/line may help with oil splashing).
2) Loosen the PS/SLS pump line banjo bolts and drain the pump and reservoir (good time the replace the reservoir filter 32411128167 and filter seals 32411137778).
3) Retighten the PS/SLS line banjo bolts with the old seals in place.
Flush system:
4) fill reservoir with Pentosin 11s.
5) start engine and turn the steering wheel lock to lock several times to flush steering box and SLS lines with 11s.
6) Shut off engine, remove the PS/SLS line banjo bolts, drain and discard the mixed Pentosin 7.1/11s.
7) replace the PS/SLS banjo bolt seals and reconnect the accumulator flare fittings.
Refill with Pentosin 11s:
8) Refill reservoir with Pentosin 11s, start engine and monitor reservoir level refilling as the SLS system charges the shocks and accumulators.
New Conversion Service: (PS/SLS system does not have a maintenance cycle)
9) However, I will drain the PS/SLS system and refill with fresh Pentosin 11s after 3-4K miles (increase 11s purity for the long run).
10) Drain and refill Pentosin 11s @ 60K mile interval.
 

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For my non m5 touring, the level height adjuster on the left hand side / muffler side has a bleed nipple on the end so I presume you bleed it like brake callipers using the nipple on the level adjuster?
The SLS adjuster bleeder can be used to discharge the accumulators however more needs to be done to drain oil from the shocks to completely drain the SLS system, to do that the lines at the accumulator or shocks needs to be disconnected and the shocks piston need to move.
 
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