bruce7

Did the oil service this last weekend including transmission oil.
Not hard just a little messy. I put about 20k miles per year on the car
so I change the engine oil about 3 times per year and the transmission
once per year. During each engine oil service interval I use the Lubro-Moly
Jectron and Ventil Sauber products to clean the fuel injection and valves.

Although I do the transmission oil change myself I use the Mobil 1 PTX
transmission oil which is available only from the Porsche dealer.
The dealer will sell the Mobil 1 PTX from their 20 liter container if you bring
your own 1 gallon (4 liter) container. A Crystal Geyser water bottle with a
screw cap makes a good container and costs about $1 from the grocery store.
Mobil 1 PTX is the factory fill.

Here's a short writeup on doing the transmission oil change.
A few pictures can also be found at:
https://picasaweb.google.com/bruce.c...mG4JXhzZ7YgAE#


Parts Required

4 liters transmission fluid (Mobil 1 PTX PN ABUL000-043-204-20)
Drain plug seal ring (900-123-118-30)

Tools & Other Materials Required (Assuming car is already lifted)

Oil drain pan
Waste oil transport container
Oil transfer pump
1/2" breaker bar
3/8" torque wrench
1/2" to 3/8" socket adapter
Phillips screwdriver
10mm hex socket
Gloves
Cardboard to lay on
Brake cleaner

Costs Involved

Cost of Mobil 1 PTX was $34.00 per liter (2012). This is up a little over 2011 when it was $29 per liter.

Pennzoil makes a good oil transfer pump for about $10.

Procedure for Changing Transmission Oil

Drive car several miles to warm up transmission
Note date and mileage
Lift car
Remove transmission undertray
Crack open the fill plug with a 10mm hex socket but do not remove yet
Remove drain plug with 10mm hex socket and drain transmission
Clean the drain plug and replace the seal ring
Install and torque the drain plug to 30Nm
Remove fill plug and insert hose from transfer pump outlet side
Insert hose from transfer pump inlet side into the fresh fluid container
Pump approximately 3.6 liters of fluid into transmission slowly until it overflows
Install fill plug and torque to 30Nm


Finish Up

Replace transmission undertray
Lower car
Road test car
Dump waste at waste oil collection center
Wash the transfer pump and hoses with soap and water, dry and store

IXLR8

Bruce, I just Googled Mobil 1 PTX 75W-90 to see what is so special about it at $34 per liter and came across the Suncoast site showing a jug (no size listed) for $34.

horse11

Hi nice write up, only thing I could add would be to turn the rear wheels to let the oil settle before you finally put the filler back in. Its a big void in there , Horse

Quadcammer

just use mobil 1 delvac. Its $40 a gallon

Slow Guy

I don't understand this. Reason?

horse11

Hi, I find it difficult at the best of times to fill the gearbox with the correct amount, its a slow fill. If you just fill until it runs out then turn the rear wheels the level drops so you can add more oil. Hopefully the correct amount. Horse.

Ocean Blue C2S

I did like Quadcammer and used Mobil Delvac, found it at a truckstop. Shifting improved! No need to dod this once a year, just follow the manual: once every 30K miles unless you have someone grind the gears in your 993...

Bert

bruce7

I'm not an expert on engine or transmission oils, but from what I've read
you would be better off using Mobil 1 PTX which is a GL 4.5 oil vs Delvac
which is a GL-5 spec oil, especially in a transaxle application like in a Porsche
or Ferrari that also includes a limited-slip differential.

Attached is the product sheet for Mobil 1 PTX.

Here is the product sheet for Delvac:

http://www.mobil.com/USA-English/Lub...0_80W-140.aspx

Also, note that the 997 User Manual on page 290 specifically calls out the
Mobil 1 PTX oil:
http://www.porsche.com/all/media/pdf...rrera_PCNA.pdf

And I may catch flak for this but here is a short writeup on gear oils from
Wikipedia: http://en.wikipedia.org/wiki/Gear_oil

Yes, all things being equal, the cheaper product might get the nod.
But they're not equal..so you get what you pay for.

-bruce

Quadcammer

until you can show me how ptx is better with factual evidence, you may want to go easy on these type of comments.

bruce7

Well for starters, just compare the viscosity numbers at different temperatures.

IXLR8

Bruce, is this concern related to ease of shifting or other reasons?

e9stibi

I get Mobil Delvac here for quite a while:

http://www.lufteknic.com/Merchant2/m...ode=lubricants

You just need one jug which costs 42.50 plus S&H

mongrelcat

^^ Nice deal.

You can also get it at Grainger over the counter (if you have an account or if they're willing to do a courtesy sale.) But it's gone up in price by quite a bit since I last got some.

http://www.grainger.com/Grainger/MOB...Gear-Oil-1MRG1

GTgears

https://rennlist.com/forums/993-foru...for-993-a.html

Read this thread and draw your own conclusions...

bruce7

From the product data sheet:

Mobil PTX provides the following benefit: Excellent low temperature fluidity, giving easier gear changing from cold over conventional SAE 80W-90 and 75W-90 grades.