1999 Boxster manual transmission fluid change

[Vidyashankara]

Originally Posted by Anker

Overfilling puts an extra load on the gears inside the transmission. You can draw it down without a lift. Floor jack and jack stands do the job.

I will try and do this in the next couple of days. I still need to remove the aluminum tray and diagonal brackets covering the transmission right?

[paulofto]

Originally Posted by Vidyashankara

I will try and do this in the next couple of days. I still need to remove the aluminum tray and diagonal brackets covering the transmission right?

Save time, effort and a lot of potential alignment issues and drill an 2" diameter access hole in the tray. You'll be happy you did.

To remove just a little fluid, remove the fill plug and jack up the from end, some fluid will leak out the fill hole and then level the car and see if the 11 mm difference is met.

[Vidyashankara]

Originally Posted by paulofto

Save time, effort and a lot of potential alignment issues and drill an 2" diameter access hole in the tray. You'll be happy you did.

To remove just a little fluid, remove the fill plug and jack up the from end, some fluid will leak out the fill hole and then level the car and see if the 11 mm difference is met.

Awesome, thanks! Can you explain the potential alignment issues?

The hole will give access only to the drain plug right? I am not sure if i can access the fill plug without remove the tray.

[paulofto]

You should be able to get at the fill plug with the tray in place. It may be a bit awkward but accessible. The fill hole for the 6 speed is more accessible.

The alignment issue comes into play when the tray is removed. It is a bear to get back in and align it with the bolt holes in the two support arms. Wrestling it back in is a pain and could result in things not lining up correctly.

[rick3000]

I spent a few hours researching the transmission oil for the '99 before I changed mine. Porsche really went all out on the early five-speed's and the oil is in fact specific to the transmission. It's a shame most dealers will try to sell people the wrong fluid, because they don't stock the 20L drum. Don't trust the parts guy at the dealer!

Originally Posted by Vidyashankara

Awesome, thanks! Can you explain the potential alignment issues?

The hole will give access only to the drain plug right? I am not sure if i can access the fill plug without remove the tray.

The plate is part of the suspension system, it acts as a brace between the rear suspension, and when you remove it, you can change the alignment of the car. If you choose to remove it and not drill a hole, use jack stands and not ramps. By taking the weight off the wheels you will reduce the chance of messing up the alignment. When I removed the plate I used stands, and when I had my alignment checked afterward it had not been affected.

[Frodo]

Originally Posted by rick3000

You definitely want to use the OEM Porsche transmission fluid, it is specific to the transmission, and people seem to have issues using non-OEM fluid. The PN is: 000 043 304 71. I do not think it is available in individual liters anymore, you have to buy a drum of it. However, Sunset Porsche sells it by the liter (they fill up empty/clean oil cans). You will need 3 liters, which runs about $80. If you try to buy it at the dealer, don't let them sell you anything other than that part number, it is not the same.

I was due to change my transmission oil ('01 S, ie 6 speed), so I gave my semi-local Porsche dealership a call. Turns out what they sell for DIY purposes is Valvoline 75W90. I guess I'll check with the folks at Sunset. In the 101 Projects book Wayne also mentions using Mobil Delvac Synthetic Gear Oil. Anyone have any experience with it?

Originally Posted by rick3000

The plate is part of the suspension system, it acts as a brace between the rear suspension, and when you remove it, you can change the alignment of the car. If you choose to remove it and not drill a hole, use jack stands and not ramps. By taking the weight off the wheels you will reduce the chance of messing up the alignment. When I removed the plate I used stands, and when I had my alignment checked afterward it had not been affected.

My driveway is sloped. When I do an engine oil change I point the car uphill then back it onto homemade ramps. By finessing it a bit I can get the car nice and level and still have access to shimmy underneath and reach the drain plug & filter.

With changing the transmission oil, if I did the same thing but, instead of using ramps, jacked the back end up and then put it on jack stands, could I avoid the potential alignment issues? The other thing I'm wondering is this: I feel very safe under the car on the slope using the ramps for doing an engine oil change. OTOH I'm suspecting it may be a bad idea to use jack stands on a slope, even a pretty gentle slope like what I'd be working with. Actually, if I do it right I can have just the front end of the car on the sloped part of the driveway while the rear end (where the jack stands would go) is still on the flat part.

When you guys have done the transmission oil have you put the car on stands on all 4 corners? (I wish I'd bought a lift years ago... )