Jacks911

The ZF trannys - both 4 speed in the early cars - 968 & 964 where of one type (internally) also used by Audi and others. Was often called one of the most reliable Transmissions in a Porsche. The later TIP S models with 5 speeds where also ZF. The TIP control Logic is in all cases a Porsche / Bosch partnership. All these had 5 Maps for Shift program. As with everything the new models get new technology and the MK II with its larger 3.6 engine benefited with the use of the heavier and stronger BMC unit with a new designed TIP Brain. The Porsche Pano publised lots of details of the early TIP transmission and Porsche published a "Technik" Service Information booklet with more detail - that I referenced on the Lock-Up.

Some facts from Technik: (and note this is in the "normal" shift 3 of 5 Program)
No lock in 1st gear; 2nd locks at 36mph - opens at 14 -
3rd lock at 40 mph - opens at 22 - --- 4th locks at 45 mph - opens at 30.
The other shift programs Open and Close at varied MPH ... Program 5 higher speeds - Program 1 at lower speeds. I am assuming this is similar in the later TIPS but woud vary based on the engine size and Model year changes. The TIP is an inovation that almost every auto maker copied with in a few years.

hind

Interesting, but I def feel mine lock up at ~26mph in 2nd, every time. Hope mine is working properly.

Spokayman

My Tiptronic is acting in a way that seems odd to me, but might be part of the normal torque converter logic. I guess I have the ZF trans in my '01 C4.
As opposed to what several previous posters noted above about issues during deceleration, my issue is during acceleration and upshifts. When I accelerate moderately from 2nd gear and watch the tach rise, there is a point where the RPMs drop several hundred RPM, and then they rise again in relation to speed and the trans shifts to third gear. It is almost like there is a 2.5 gear. This does not happen in any other gear.
The trans shifts very well and seems to follow the logic that others describe regarding the other shift programs that depend upon how aggressive I am with the throttle.

Anybody else experience their Tip acting this way?

Spokayman

Well, the mechanic seems certain that this is just the torque converter locking up in a normal fashion.
He says this is normal behavior for the trans, but I think he is deducing this from info he read online somewhere.
It would be nice to drive another tiptronic car or hear from someone else with a Tiptronic about their experience.

sjfehr

Mine acts a lot like that at moderate acceleration, too. I think you notice it only in 2nd because you're not going fast enough to have it happen in 3rd. If you accelerate harder, the torque converter should not lock up. If you accelerate softer, it should not be so noticeable.

In a slush box, the engine's always moving faster than the wheels, that's how it converts torque; when the lockup engages, that rotating momentum in the engine is thrown instantly to the wheels, giving you a bit of a rough shove. I've never watched the tach, might have to tomorrow; but I'd expect the engine to momentarily slow down, just like you described.

So: quick fix: BURY YOUR FOOT TO THE FLOOR! Lockup doesn't engage so long as you're in kick-down, and it's more fun, too

Spokayman

Thanks for the response sjfehr.
Actually the torque converter locking up is not something that I really can feel. The lockup is pretty soft. Looking at the tach is pretty much the only way to tell its locking up. In fact it was a few months before I noticed it and it was observing the tach that caught my attention.
I'll have to try different throttle applications to see if I can get it to lock up in other gears.

RDCR

Yes mine does the exact same thing, totally normal according to my indie.

CarlosCA

Also have been very pleased with tip. Use manual mode 99% of the time. Had a minor issue diagnosed last year and service manager at dealer agreed the MB five speed is pretty much bulletproof...good to hear.

Spokayman

Thanks for the confirmation RDykmans.

CarlosCA, I have heard the same about the durability of these transmissions.

I drive most often in manual too especially because of the tendency of the trans to shift up to a higher gear causing engine RPMs to be too low.

I have found that for a full acceleration run from a stop, it is best to leave the trans in automatic mode as the shifting logic is very good, and the shifts somehow seem better timed than I can do manually.
Other posts have indicated that when tracking the car the automatic mode is also pretty much the best way to go. I haven't tested that yet tho.

sjfehr

The tip is pretty smart about learning your driving style. On the track, it senses kickdown and should automatically go to the most aggressive mapping. It's a little more subtle when you're blending normal low-key daily driving with moments of passion. Teaching the tip with a few manual downshifts when it's not aggressive enough and upshifts when it's more aggressive than you like seems to help it pick a good shift map that fits your driving style.

RDCR

Mine automatically upshifts the same whether in A or M under hard throttle, agree the shifts seem quicker letting the car do it under hard acceleration. I have not tried A mode on the track yet to see if the downshifting works as advertised when the transmission goes into sport mode. I installed a carnewal RAID wheel with true up/down paddles which makes the tip seem a little more functional. At least now I can hold the wheel properly and shift vs those worthless stock buttons!

Jacks911

Note to HIND ... and all - My post back in 2011 offer some info that was taken from Technik publication for the first Tiptronic. This was the ZF in the 964 and 968 back in 1990 to 1995. So while it give us some insight to the way the system is designed ... much has changes since then. I think all of you are relating normal behavior, and a lot of this can be related to your personal driving style and the terrain as well. Don't forget this system knows when you are going up and down grades and cornering. It reacts to many different inputs. Just remember to say "Thank you Hal" at the end of the drive.

Shaneesprit

Hi seems like some knowledgeable guys on this forum, well let’s see 😊

C2 2004
ok so my Tiptronic is playing up, I have not really looked into it yet, but I have lost drive a few times, but at the same time I lost the gear indicator on the dash, well the first time it happened I did, on the other occasions my dad had stolen my 996 from his garage and seems to believe the car is shared! 😂 so I wasn’t there to confirm this is the case.

so I was thinking possibly electrical issue, but also note someone had noted a low oil level May cause this, and that would tie in with the torque converter trying to lock on while cruising at low throttle, which is the point this has happened.

so if the gearbox were to loose power would the drive be lost? Or am I looking at an oil / box issue?

Jacks911

[QUOTE=MetBlk 911;8195052]Thanks htny, I'm enjoying the history lesson. So what make the ZF tranny "old school" and the DC one of the best ever made? Better reliability? Better performance? Better feel?

I drive in manual tip mode 90% of the time. I only use "Drive" when I need both hands (ie: coffee in the morning). [

Best understanding for the move to the MB Transmission was that the 996.2 and later Carreras had 3.6 motors and higher torque. And so Porsche, typical over engineering, looked to the future with possible need for that. Another likely reason is they needed that MB Trans for the Turbo so why source Transmissions from Two vendors so the 2002 Carreras got the "Bigger" trans. And as they had a new and more complex control unit (as noted) that same controller went in all models.
The ZF unit was and still is very reliable - just "OLD" in the sense of Porsches constant improvement in it quest to make every new model just a bit better & more powerful, faster, etc.

theprf

You might have started a new thread with your issue, it may have attracted more attention.

If the lights on the instrument cluster go away I believe the culprit is the switch on the gear selector lever. This gets a lot of use and can get coffee and such spilled onto it as well. If the switch on the gear lever isn't working properly the TCU has no idea what gear the trans should be in. I believe it's quite an expensive part; perhaps a used one might be in order. Or you may be able to open it and clean it.
The other electrical problem that can happen with the MB 722.6 is the conductor plate in the transmission itself can go bad, this usually results in throwing codes and the trans going into limp mode. The D and M leds on the cluster flash alternately if the trans goes into limp mode and you have only 2nd and reverse.
With any automatic if it's low on fluid it can misbehave. Checking the fluid isn't a cakewalk, you need to get under the car with the engine running and open the upper filler port on the drain pan. The trans temp has to be between 30-40C. The you can add fluid if needed while the engine runs, and close the filler with a new copper washer before you shut the engine off.