Hydraulic oil for convertible top motor

[ckeasterling]

The hydraulic motor that drives the top on my '99 996 Cab is "groaning". It was making this noise when a bought the car a few months ago. I checked the reservoir and the fluid level is below MIN so I'm hoping that's the problem. I called the closest dealer (120 miles away) and they don't have any in stock but will order some at $20+ for 250 ml. Question. Do I have the use the official Porsche hydraulic oil or can I buy something locally that will do the job?

[Tool Pants]

I am a Boxstir guy so I have no clue since our top is 100% electric. But I did know that that at least part of the 996 top system is hydraulic. So I got curious.

The 996 part number for the 250 ml container is 000 043 204 89. On the 996 part list it does not tell you who makes it. But if you do a search on the part number it is also used on the Carrera CT for the rear spoiler, with the words VITAMOL ZH-M next to the part number. And I thought the CGT spoiler was electric.

Do a google search for those words.

I came back with the company name Aral from German with a .de address but there is also a .com address.

http://www.aral-lubricants.de/

http://www.aral-lubricants.com/lubricants/com

Brake/clutch, power steering, and the tip transmission all use hydraulic fluids. But it looks like there is some special stuff for the top.

[djantlive]

For $20, I'd use Porsche's oil. It's not worth using something else. Where do you fill this?

[ckeasterling]

Thanks Tool Pants. I verified with the Porsche dealership that the hydraulic fluid for the top motor is the ZH-M type. I found that Mercedes uses the same oil in their hydraulic suspensions and convertible top motors. A liter was $17 at the local Mercedes dealership. The part number is 000 989 91 03 10. Incidently, topping up the reservoir fixed my problem.

Also, to answer the question about the pump motor location. It is behind the rear seats. Partially raise the top so the rear cover is fully extended. Release the two cables from under the back window and fold it forward so you can access the area behind the rear seats. Remove the interior trim cover to expose the pump motor, lines, etc. The pump motor has a clear reservoir on the bottom. There is a a hex head plug in the fill hole right above the reservoir, between two hydraulic line fittings.

[a1certified]

How do you release the two cables that hold the top in the rear? Do you just yank on them until they snap off? Or do you need a tool of some sort?

Thanks,

David

[capt601]

the two rear cables are basically just pulled off. It is like a ball and socket joint. It does take some pressure to separate the two pieces, but it is not too bad. very easy to push the two parts back together once you are done.

capt601

[Izzy]

You can see how they come off in thid DIY. I have used John Deer hydraulic fluid for well over a year, without any problems. But Porsche fluid is the recommended.

http://www.renntech.org/forums/index.php?showtopic=6967

[a1certified]

Great. That's what I was hoping. I'm going to give it a try this weekend. Otherwise, I'm afraid I've got a little repair bill coming up.

[Swaller07]

Easier than I thought it would be...Instructions are spot on. The Nut was a little tight so I recommend hitting it with some wd-40 and using an allen wrench extension to get more torque on it. Works great!!

 

P.S. I used Porsche oil and paid $30 after a discount from the service guy. It was $40! Still the best price YET on anything for this car...

[alabamatoy]

Pentosin CHF seems to work fine.  Its readily available from most el-cheapo car parts chains.  I am told that Pentosin CHF is what most of the German marques call for, all except Porsche.