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Discussion Starter #1
Hello members,

before joining I have been searching info here and there and did learn few things about this system. I'm looking to get a euro 93 M5 but the car has the front shocks completly shot and I know this is a self contained gas/fluid with the sensors/selenoids attached to them unlike the rear unit which has the selfleveling setup and use the accumulatros, pump etc.

Question is, what fluid does it use, Pentozin or the "ATF/power steering red" fluid and if it works from the p/s pump or only the P/S reservoir? Or it's a separatly system?

I found that some grease monkey tried to attach a aftermarket pressue hosue the from one accumulator to the rear shock and it's leaking. The car has about 150k kms on it and it's overall in good shape.

The front struts are expensvie, but I think I got a good deal (if I buy the car) for the front shocks. Just wonder how do I bleed the system exactly and if there is any diagram for the hidraulic system for the EDC and electronic diagram.

Also, found that the MAF was probably adjusted or something ( dunno if it's adjustablea at this point) but had some 2.5% red mark son it. Drove the car and found it was running rich at some spots (black smoke). Did a compression test and got 200 PSI average in the 6 cyls, woudl be this good enough?

Thanks for any input!
 

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Pentosin is for the power steering system and self leveling. They share. The one reservoir in the left front of the engine compartment. Use the fluid labeled on the lid. I hear the two are not mixable.

The front struts do not use any fluid, im not sure if that is what you are asking.
 

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Fronts are completely sealed units. Rears use pentosin CH-11S. I always thought the fronts use a mixture of fluid and some sort of gas. Brand and type of fluid and gas are unknown as far as I know. Then there is the inside pressure which we don't know. If I would give any advise:
1) If you WANT the EDC system > Buy new struts including the the whole assembly (top mounts, pads, springs, hub and bearings). The shocks last between 60.000 KM and 100.000 KM depending on driving conditions.
2) Otherwise go for an aftermarket setup (Bilstein, Dinan etc....). Lots of posts here on the forum around this subject

Personally i would go for the EDC setup. Not because it's so much better then option 2 but because this is part of the nature of the car:):)
 

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Discussion Starter #4
Thanks for the advise. I think I have seen some red fluid in that aftermarket pressure hose/tube from one accumulator to the rear shock (hack job) rather than the ******/yellowish Pentosine fluid, unless the Pentosin is red like the ATF as well? Hoepfully the rear shocks are OK still.
 

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The fluid should be green .

The 3.8s typically run Pentosin CHF11S .

The 3.6s typically run Pentosin CHF 7.1 .

Both are green .

Drain that other sh*t out asap and flush through with Pentosin of the grade mentioned on the PAS reservoir cap ......... The system is self bleeding , so simply top up the reservoir to just below the gauze , start the engine and slowly turn the steering wheel to almost full lock on each side whilst keeping an eye on the Pentosin level in the reservoir and topping up as required .

D
 

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++ And on top of that make sure the rearshocks get really flushed. A simple disconnect from the flex hose on the shock is not enough. Knowing for sure you got the wrong fluid, it's better to seperately move the shock up and down to release all the rubbish in there.

Cheers

W
 
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Discussion Starter #7
Thanks for the input. I was trying to find the info but I couldn't. Since I'm going to flush the whole system, how many cans of CHF S11 Pentosin I would need? Checking my inventory I foudn two brand new cans ( 1 litre) and I have two other cans (1 litre), but used, one has about 1/4 and the other barely 1/2 level. I ask this because before order more fluid I need to check and test one thing in my rear EDC shock before waste my pentosin.

Thanks
 

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Hi Diego , the 3.25 litres that you have should be more than enough to totally flush and renew the CHF11S .

D
 

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Discussion Starter #9
Thanks for the input David.
 
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