Hydraulic fluid $25.00/Qt? - PeachParts Mercedes-Benz Forum

Daytonaman · #1 11-18-2005, 01:05 PM

Is there any comercially available hyd. fluid for use in the power top reservoir?Can ordinary power steering fl. be used or is it MB only? 92sl500.

LeaUK · #2 11-18-2005, 02:55 PM

I've recently replaced mine and the advice across this forum is to use MB recommended fluid ONLY. Just image if you saved $20 and next year you find all your seals have eroded away and replacement of all hydraulic components is required. I recently replaced mine with MB fluid for 8quid (that's 16USD) - it was a 'no brainer'.

There are some things you shouldn't risk!

Lea

R129 - Soft top hydraulic fluid

Carlos Serrano · #3 11-18-2005, 03:03 PM

Paid 32.00USD in Albany Ga. MB dealer, tax included

Daytonaman · #4 11-18-2005, 03:41 PM

I knew that. I just wanted to read it. I' m replacing some leaky cylinders and am wasting a lot of fluid. Had three small ones fail and I'm down to the small one on the drivers side down under. Someone before me probably used the wrong fluid. I think that one is expensive. It's not hard to relplace after you disassemble the whole car.

kip Foss · #5 11-18-2005, 10:00 PM

I bet if you asked a few oil company tech. reps. they could tell you if the MB hyd. oil is special. I have serious doubts that there are any seals or O-rings in the BM system that are so special that they require a one of a kind oil. I would bet good money that any name brand hyd. oil will suffice.

I run two 2K ton per hour bulk ship unloaders. All systems on them are hyd. There is a total of about 1,200 hp worth of hyd. systems on each machine. When we are unloading these machines run 27 hours a day 9 days a week flat out and under max. load. We use Mobil DTE 25 and have never had a hyd. oil related failure. We have failures because of the dirt that gets into the system but the oil never breaks down. I can't believe that the MB rag top system is harder on it's oil or the seals are more touchy that on my unloaders.

MB tells you to use their oil because most MB owners are anal about maintenance and they will but anything that MB says they have to have. Get a look at their can and see if there is a Mil. spec. number on it. If there is then you can get the same oil for 1/10th the price at a parts shop. Ask a tech. rep. at Mobil what he knows about MB oil and see what he says.

nobby · #6 11-18-2005, 11:13 PM

THAT was a good comment...

Strife · #7 11-18-2005, 11:41 PM

I think that a lot of this goes on in the car business, and not just on MB's. I had a MB service mgr tell me that Dexron III was just fine for the power steering system, for example.

I wonder how much your ship unloaders cost relative to the MB convertible top, or how much they cost per hour of downtime.

kip Foss · #8 11-19-2005, 11:07 AM

Strife,

The unloaders are about $45 million each and if we have a ship at the dock down time costs about $500 an hour PLUS the ships demurrage which costs from $12k to $35k a day. For that reason we have to use the best hyd. oil.

What I am saying is that there are few machine out there, regardless of size, shape or use, that require hyd. oil that is so far out of the ordanary as to cost $25 a qt. For systems that operate at or below about 10k psi seals, packings, hoses, etc. are all about the same. MB doesn't have anything in their systems that is so exotic that it needs some sort of hand made oil. What they do have is an anal clientele that thinks that only MB parts will work on MB cars.

Mike Miller · #9 11-19-2005, 11:13 AM

I'm with Kip Foss. A few years back no one made synthetic motor oil for Harley Davidsons. Everyone was afraid to even use anything but Harley Oil, because of the V-twin design and heat of an air cooled engine. Then Mobil came out with an synthetic oil specifically designed for V-Twins at a very reasonable price. Harley said, Oh Crap, these guys are going to cut into our fun money!!!
Now Harley has a synthetic oil, which, of course, they recommend as the only oil you use.

I am in the aerospace business. Check the MB can for the MIL SPEC, if there is one, and go get the same from Auto Zone!!

Daytonaman · #10 11-19-2005, 01:09 PM

Forgot all about 25 dollars per Qt. when I priced the one of the leaking cyl. MB wants BIG money for these parts. These things should be able to be rebuilt. I located a place in Mich. that claims to be able rebuild any hydraulic unit.

kip Foss · #11 11-19-2005, 06:20 PM

There is probably no component in the MB system that can not be rebuilt by the average hyd. repair shop. The pump unit in the MB system is basically the same as in a 1955 Chevy convertable. It has a pump, a relief valve, a directional valve, and a couple of solenoids. What's the big deal? Any hyd. shop that repairs Portapower rams and pumps could surely fix one of these units. They may have to get the parts from MB but I doubt it. MB probably gets their hyd. from Rexroth or some other German manufacturer. Most hyd. shops should be able to get these same parts.

The rams are the same way. They have a seal on the rod end and some packing on the piston side. You unscrew the seal carrier, pull out the piston, but in new packing and a seal, reverse the vedio and off you go.

I deal with hyd. systems all the time and none of the components are all that difficult. The electrical system that operates these units is a different thing. That calls for a great deal of know how.

waybomb · #12 11-20-2005, 08:54 AM

I know for a fact certain oils can not be mixed with certain other oils, especially some synthetics. I am guessing this Benz hyfdraulic oil is a synthetic.

I am not a lubrication engineers, but they have have all types of super-refined oils such as Polyalphaolefins, esters, alkylates napthalene, and many others.

Just be careful.

kip Foss · #13 11-20-2005, 09:24 PM

MB has had this hyd. system since they have been making convertables and I doubt that it has changed much, except for a few whistles and bells. I am sure that the seals and packings have been updated but I doubt that the system is now so sophisticated as to require some space age oil.

If the pump or a component needs repair the entire system needs to be flushed. After it is flushed then any modern hyd. oil could be used.

LeaUK · #14 11-21-2005, 07:02 AM

I think we all agree that there's nothing special about MB oil apart from you automatically receive the exact grade without having to research the OEM and the MIL spec etc, etc. However, I think you may have missed the point.

At 8 GBP for a once, maybe twice lifetime fill, it's hardly worth even researching (unless you are indeed anal about oil). Handover the cash and worry no-more

- It's a no-brainer.

Of course things would be somewhat different had this been a regular service part...

Lea