Greetings all and Happy New Year.

How do you check or add tranny fluid in a W215 CL500?

I have a low level 'hum' or 'drone' sound when accelerating from 5km/hr - 85km/hr. Above 85km/hr and up the car is quiet.

Any help or insight is appreciated.

The trans doesn't come with a dipstick. So you would need to buy a special tool to check it.

Doubt if the trans would make noises & then go away.
Possible a worn trans mount OR motor mount would cause that.

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Thank you Doc.

How would I go about locating the worn mount?
Is this a common problem?
Is it possible it could be the power steering pump, even though I hear no sounds when turning the steering wheel?

Any further insights would be greatly appreciated.

Thanks again.

I forgot to ask--how can I get the special tool for checking the tranny fluid and how does such a tool work?

Yes, a servo low on oil will make noise. Just check the level.

About you autobox, whch should be a 722.6, read this;
http://www.peachparts.com/Wikka/Trans7226Fluid

br,
syljua

__________________
1998 CL500 W140
1984 230E W123

Syljua,

Thanks for the great help. I have topped up the ABC with Pentosin oil fluid (is this the servo you are speaking of?) and yet I still hear the drone. I was wondering if this is normal and/or just the sound of the drivetrain or maybe a low tranny fluid noise.

The tranny link is excellent. Thanks again. Is this procedure usable for our w215 transmissions also?

I've found the 'servo' dip-stick I think you are referring to. It is for the power steering 'oil' of course....d'oh!

Anyway I've checked the dip stick and it IS below 'max', so I will try to get some MB power steering fluid and top up tomorrow.

I've also located what I think is the tranny fluid dip-stick and it has a cap with a red band in it and says 'MB service use only' or something like that.

I am now a bit more knowledgeable about my car.

Thank you very much.

Fixed it! The 'drone' is gone.

It was the ABC Pulsation Damper/Accumulator. Part as less than $200 cdn and 1 hr labour.
No more 'hum', 'drone' or vibration.

The MB STAR SERVICE Service Manual Library DVD states in the DTB....

The ABC Pulsation Damper/Accumulator can correct a 'hum' or 'drone' sound.

If a 'hum' or 'drone' sound up to 2000 rpm is heard, but gets drowned out by the sound of the engine above 2000 rpm, it could be as simple as the hydraulic lines contacting the body of the car.

Have the lines inspected and if they clear the body, then replace the Accumulator.

The dvd manual also specifically states that replacing the ABC/PS pump will NOT correct the 'drone' sound problem.

I highly recommend buying the DVD from the dealer. It has all repair and maintenance procedures, diagnostic info, function descriptions, wiring diagrams with component locations. Service bulletins and DTB. $100 cdn.