1996 Tiptronic service (drain/fill/filter and gasket change)

[tshih]

Hi,

About to do a 45,000 mile transmission fluid /filter change for wife's 96 993 with tiptronic. Need to know what fluid is recommended (Dextron #?), how many quarts, any potential problems? Where does one fill the system (through the dipstick hole?

[Don Haney]

Hi there,
I used the swepco 714...

Swepco 714 is specifically designed to be used in heavy duty automatic transmissions from manufacturers such as Allison, Renk and ZF (Zahnradfabrik Friedrichshafen), as well as CAT's TO-4 drive train specification.

It improved the shifting on my 91 C2 Tip. My 91 had a quick fill provision on the side of the tranny. Call me up for some 714 and I'll look it up for you...
Good Luck,
Don

[tshih]

Thanks Don for the info. However, in pricing each candidate (Swepco 714 in 10W or 20W..don't know which is best), Dextron II D (no longer available and superceded by Dextron III E) was factory fill, Mobil1 ATF was the best and has the price advantage over Swepco (no shipping costs since it is at local Pepboys $6/qt).

So I will be going with Mobil1

[JWPATE]

Out of interest, did you resolve the fill problem? From memory, the manual advises to use a "quick-fill" adapter on the side of the transmission. I have wondered how I shall get around that. Perhaps one could remove the quick-fill fitting and use a plastic or rubber tube to fill it.

James

[Don Haney]

That's what I did and also how the factory recommends to do in an emergency fill situation. On my first C2 trans service my Porsche mechanic cracked my quick fill, so the fact tool was useless.....

[JWPATE]

Thanks Don,
I should have known that you would have "been there".
James

[tshih]

I haven't had time to do it but will try this weekend. I have a hand pump with plastic lines for filling the side of a manual gearbox (pumps 90W hypoid gear oils), also a clean Brake bleeder (hand pump pressure unit) will work as well if you remove the cap that adapts to the BF reservoir.

[JWPATE]

Good tshih,
That is what I also plan. Do remember that temp. is important in deciding where enough is enough.
James

[tshih]

The owner's manual says about 10quarts is the change capacity. I always carefully collect and measure how much comes out of an automatic trans and replace the same amount when doing a service. The density of the fluid does vary with temperature so i intend to do it while hot (after a warm up drive) then top up to correct fill mark after warm up again (both engine and trans fluid change service).

[Don Haney]

FYI-The factory revised the fuild levals for the tiptronic. They raised the leval, but dont remember how much...

[tshih]

Well I wouldn't overfill any automatic since that will rupture seals and cause major problems. I would err on slightly low rather than high in any case. Did you say the tranny case has a sight glass indicator for the level when hot?

[JWPATE]

Oh no, no, no,
I do not agree. You will not rupture any seal I can think of, in the Tiptronic by overfilling. Pray tell, what seal could rupture as a result of overfill? That is nonsense. Actually, there may have been automatics where that statement may have been correct, but I cannot recall a single one. What you will do in all units, with an overfill situation, is cause a leak to occur. The fluid level will exceed the sealed input and output shaft levels and the particular transmission will drip from other openings, such as shift-linkage holes, not normally sealed against fluid loss.

On your suggestion for filling the Triptronic transmission through the dip-stick hole, well, to be polite, just where do you expect that hole to be? Don, and others on this forum, reasonably expects that you have already read the owners manual, if not the service manual, before asking advice. There is no dip-stick!

With regard to your suggestion that one should “err on the low side”, I would agree with your position, but with some argument. Yes, generally any automatic transmission is better off not to be overfilled, as it leads to leakage. However the Tiptronic in your C2 is no ordinary transmission. Times have changed, and so must we. The fluid in your C2 Porsche automatic transmission requires external cooling. It is, in my personal view, the finest transmission available on any Porsche; but it cannot run without a cooler. Therefore, you are very, very far off-base in thinking that one should “err on the low side” in this case. Have you taken the time to become aware of the ATF cooling radiator? It will be found in your front right fender, and it receives ambient air BEFORE the engine oil cooler? Still want to “err on the low side”? Go ahead, it’s your money.
The Porsche position on this was (and is) to not err at all. To check the transmission level, you will need to accept the necessity for dirty fingers. You must get the car up on a lift or on safe stands, with the engine and all fluids at true operating temp. (15 min drive – minimum). Then:

- remove underbody cladding
- vehicle must be HORIZONTAL
- engine running, at normal temp
- hand brake on
- selector in position “p”
- With Bosche hammer tester 9288 check that the ATF temp is at 80 degrees C. (don’t have a hammer? Probably too bad Charlie! I got one of the last ones. In your case... keep it hot!!)
- With engine running, add fluid until the sight gauge on starboard side of transmission is above min and less than max.

OK, now to Dons note that there was a change (he is always right):
Porsche Note:
The ATF capacity was increased by 0.51. The ATF level therefore rises and the 80C check marks move further up on the oil level tube.
NOW (this is for you), make sure the fluid level is between
Maximum of 15 MM above the 80C mark and, lowest level 3 mm below the mark.
Just as Don suggested (he is never wrong), a slight increase.
Best regards,
James

[tshih]

James,

You're right with your advice.

I did read the factory service manual last sunday and yes, there was the note about the increased capacity and the new 3 and 15 mm level marks.

Yup there's no dip stick....that was only assumption before really looking at the task.

I do happen to have a Hammer KTS 300 but you'll have to send me instructions on keying up the appropriate menu to read the temperature of the tiptronic fluid. The instructions for use of the Bosch tool was rather vague and difficult to interpret (I don't read German that well).

Tom

[tshih]

Also one more thing, who sells the adapter called the quick-fill nozzle shown in the factory manual... it looks like a compression fitting that slips on the hollow capped pipe leading to the banjo elbow. Anyone can come up with a part number that I can order from the dealer? I already ordered a Motive Brake pressure bleeder to use for this job of filling the atf. from Pelican.

[Don Haney]

I have one and yep its for sale. Gotta check my C2 parts for sale list and see what I want for it. I believe I paid 45.00 at cost for it and it had to come from Germany (6 weeks)..

[tshih]

I tried to order it from a Porsche dealership and was told that it isn't a factory part. Their service techs just slip the hose directly on the pipe and their pressure gun is strong enough to push past the checkvalve spring at the end of the elbow to deliver the atf directly through the quick-fill line. So I intend to replace the clear line from the motive bleeder with one of the correct ID to fit the pipe directly.

[JWPATE]

To use your Bosch hammer tool for checking the Tiptronic fluid temp:
Connect the cable up as usual
Turn the hammer on and let it do the normal test cycle
Then you will see a menu of systems – on the second page, open Tiptronic
Another menu will appear – on the second page, open Actual Values
Go down that list until you find Temperature

[tshih]

James,

I first used the KTS301 on my 1993 RSA which doesn't have a tiptronic tranny. I've got the module thats suppose to interface with 911, 944, and 928. Never saw any menus with tiptronic label before. Anyway what module do you have and how many different ones does one need for coverage of 1990-1998 (964 and 993)?

[JWPATE]

When I power up the Hammer, the information on display is:
Porsche mod eng
Mod. intro. 01.10.95
Version 8.1

If I remove the module and examine the actual numbers on the side:
928GV
Version 8.0/10.95

I regret that I am no authority on Bosch testing equipment. On my own hammer, after I turn it on there is a short self-test and then the above mod information appears. If I then forward with the > arrow it, I get:
vehicle type
1=944
2=911
3=928
If I select 2, then I get;

Connect adapter cable to test plug. Ignition on. when completed >

If I follow those instructions then I get a message that the hammer is testing for onboard systems and a string of *** start to work off as I can hear various valves and etc. being tested. After about 90 seconds a menu appears;
1=DME
2=heating system
3=airbag
If I do not chose any of those options, but rather hit > then it goes to the second page;
1=Tiptronic

Now if yours doesn't behave this way, perhaps you should send it back to Bosch. I sent mine back once when it wouldn't charge correctly. For a very reasonable fee, they replaced the battery pack and gave the unit a thouroug checkout. They no longer make the hammer, and few Bosch types will know what you are asking about. Sooo, to save you half a day on the phone (how do I know?) there is a Bosch location in Chicago that can help. The number is 708 865 5238.

Regards,
James

[Don Haney]

Hey Guys,
Yes its a factory fill tool...Here is what it looks like...