996 Tiptronic smoothness

[n3erl]

Only had my 911 for a few weeks so still getting used to all the little idiosyncricies and wondering which noises I should or shouldn't be concerned about but heres one that bothers me a bit. When I'm slowing to stop, say at a set of lights, when it changes itself down into second there is a bit of a snatch/ jolt. Should I worry is this a "they all do that"?

[jkh112]

My 996 tip does not do that, the shift down to second is very smooth. If I shift manually down to first then I do sometimes feel a slight jolt.
I don't know how many miles your car has done, but I had my gearbox fluid changed after 10 years and 80k miles which resulted in smoother shifting (not that it was bad before!).

Edited by jkh112 on Friday 7th June 14:06

[n3erl]

Thanks for feedback. Its only done 36k but is an 02 car. Would the gearbox oil normally have been changed by now by Porsche does anyone know? (it has full main dealer history).
Mine also "twitches" if you manually go into first at a standstill

[boxsey]

n3erl said:

Thanks for feedback. Its only done 36k but is an 02 car. Would the gearbox oil normally have been changed by now by Porsche does anyone know? (it has full main dealer history).
Mine also "twitches" if you manually go into first at a standstill

ATF and filter change at 96K according to the manual. That's when I had mine done on my previous boxster and didn't notice a before and after difference.

[FarQue]

I've read that a fluid change/filter clean can work wonders on a tip 'box - but can't remember where - sorry. A slight jolt changing down to first manually at standstill was present in our 986s and 997s.

[Pugley]

I noticed smoother changes after my 996 Tip had a full sump off and clean out at about 8 years/60000 miles
There was a fair amount of sludge and condensation, I suspect mainly due to lots of short journeys.

[AlexH997]

jkh112 said:

My 996 tip does not do that, the shift down to second is very smooth. If I shift manually down to first then I do sometimes feel a slight jolt.
I don't know how many miles your car has done, but I had my gearbox fluid changed after 10 years and 80k miles which resulted in smoother shifting (not that it was bad before!).

Edited by jkh112 on Friday 7th June 14:06

mine gives the same experience, it's 8yrs old 997 with 40k

[Nineexcellence]

Well it should not be doing it. Could be a number of reasons.

- adaptions values, which can be reset so it learns again
- low ATF - the fluid in the gearbox has significant impact, even 200ml less is enough to cause major issues
- plate bolts loose - can be tightened for the shift
- gearbox service can be done at any time but better to do as infrequently as possible - you can disturb sludge that can cause issues
- value body solonoids

The TCU ( tiptronic control unit) can be read to see values which can help to determine any issues.

1st and 2nd gear is one set of clutch packs, so they could be worn, but with low mileage unlikely.

First suggest is get it on a ramp and make sure it is not leaking any fluid. The reset adaption values and potentially change the ATF.

Ken

[n3erl]

wow... pretty thorough diagnosis. Many thanks for that and just a shame you rather too far away for me or I'd happily bring it in to you guys

[FarQue]

Just to add: several years ago, when they were fairly current, I had an 'approved used' BMW 330ci sport with an automatic 'box. When slowing down to, say, a set of red lights it would 'clonk' down into second gear every time.

Local BMW dealer had it for a day and re-set everything on their clever computer and the down-change clonk was gone... I think Ken (Nine-Excellence) could be on the right lines with a 're-set', after an oil-change.

[AlexH997]

Nineexcellence said:

Well it should not be doing it. Could be a number of reasons.

- adaptions values, which can be reset so it learns again
- low ATF - the fluid in the gearbox has significant impact, even 200ml less is enough to cause major issues
- plate bolts loose - can be tightened for the shift
- gearbox service can be done at any time but better to do as infrequently as possible - you can disturb sludge that can cause issues
- value body solonoids

The TCU ( tiptronic control unit) can be read to see values which can help to determine any issues.

1st and 2nd gear is one set of clutch packs, so they could be worn, but with low mileage unlikely.

First suggest is get it on a ramp and make sure it is not leaking any fluid. The reset adaption values and potentially change the ATF.

Ken

Ken

my 997 Tiptronic normally sits in 2nd gear once I've slowed down however there are times the car is still rolling to a stop and I drop it manually into 1st and I feel a slight jolt/knock....is this correct?

[tr7v8]

Just had a fluid change & re-adaption done on my 2000 986 S @ 82K by my local OPC. Certainly a lot smoother & crisper change now.

[jamesogt]

For £120, a fluid change is a cheap way to start....

[thelandIord]

Could someone please explain what resetting the adaption values actually does.

Cheers

[tr7v8]

thelandIord said:

Could someone please explain what resetting the adaption values actually does.

Cheers

The box is intelligent so gets to know your driving style etc. & this influences the way it behaves. Readapting or resetting it means it learns all of that again over the next x miles.