Transmission snatch

[missile]

I notice the transmission snatches when manoeuvring my 981 slowly on full lock. Should I be concerned, or is this the LSD kicking in?

 

[elstonc]

Are you sure it's not the tyres? When manoeuvring mine on full lock, particularly when the tyres are cold, I get jerking movements as the tyres slip/grip on the road.

 

[Motorhead]

Hi Robert,

More details - manual or PDK transmission? The locking diff isn't standard on the 981, so I presume that it's been optioned?

Jeff

 

[CLIFFWILKINS]

All cars with wider wheels and tyres do get tyre scrubbing on full lock even more so when cold.
Cheers Cliff.

 

[CLIFFWILKINS]

Cant comment on the 981 with a LSD as Tracy's does not have it.
I know my GT3s on slow tight manoeuvring would lock up moan and groan but on that model it's normal.
Cliff.

 

[missile]

Many thanks for your prompt responses.
Please be advised: My 981 is PDK. I have driven many cars with wide (and wider) tyres, so I do know how that feels. I shall ask my dealer. No doubt the response will be "they all do that sir".

 

[elstonc]

Well you can tell him mine doesn't do it!

 

[Motorhead]

Robert,

My 987.2 Cayman has a manual transmission with LSD and I don't recognise the symptom you describe.

Perhaps there's a problem with the clutch pack on your transmission. I'm not that familiar with the PDK 'box but can you manually override it to start in 2nd gear rather than 1st gear? If you only get the problem in one of the two gears it could possibly indicate a problem with one of the two clutches.

Best to get some dealer input I think.

Jeff

 

[CLIFFWILKINS]

On very full lock first thing in the morning Tracey's 981 the front tyres scrub tyre skip which ever you want to call it.
Sounds feels awful I know but it's not a mechanical issues and won't harm the car.

 

[missile]

Thanks for the responses,

The feeling is hard to describe and it feels mechanical. You may be correct, I am fretting needlessly and it is simply tyre scrubbing. My other car has 255/45R20 and does not exhibit this "feature"

I shall report back after I have been to the dealer.

If I get the "they all do that sir" response, I shall ask to try another car for comparison.

 

[Motorhead]

Robert,

I wish I had a pound for every time I've seen the dreaded front end tyre skip mentioned on this and other forums, but it's usually associated with the autumn/winter months when temperatures are falling rather than spring when the reverse is the case.

You should be able to tell if the symptom is related to the front end (tyre skip through the steering wheel) or the rear end (transmission judder through your backside).

Hope you get it sorted to your satisfaction.

Jeff

 

[tiskev]

Is this all the time or only when you start off when cold ?

 

[BrianJ]

Mine does it all the time, forwards or backwards, irrespective of weather, temperature or anything else. Doesn't even have to be on full lock, just getting near to it. The front literally jumps across the road when manoeuvring slowly. A bit disconcerting for everyone, especially when near to walls etc. Mine has 20" wheels and is a lot worse than with my previous Cayman S on 18s. They definitely all do that sir, but worse on the larger wheels. The only significant thing I wish Porsche would design out.

 

[lawrencemoss]

On my car this is worst when reversing. Basically the front wheels are trying to go in one direction and the rear wheels in a completely different direction. Hence the front wheels get "dragged" sideways and jump in protest. Sound horrible but with slightly less than full lock, disappears.

 

[tscaptain]

The only significant thing I wish Porsche would design out.

Not sure they could as it's a function of the width of the tyres. On full lock, or near to it, the inner and outer edges of the tyre travel a different distance. As they are joined to each other something has to give! Hence the slippage.

 

[rob.kellock]

My Cayman 981 does this terribly. I was in Brendan Daly's last weekend and his was the same...

Mine is worst in cold weather, can't say I have noticed it when the tyres are properly warm.

 

[missile]

I had my 981 into the dealer today. The mechanic agreed that transmission judders when manoeuvring on full lock. I was pleased to have the opportunity to watch whilst he checked it over carefully to make sure nothing was rubbing. He said that this is a common problem, best to avoid using full lock and bring it back should it get worse.

I feel re-assured now that I know the cause and very pleased with the service from Aberdeen Porsche Centre.

 

[tiskev]

Rob is this a horrible clonking noise when on lock as my Cayenne,does it
and the dealer cant find anything wrong with car.sounds like the
drive shaft bearings have gone

 

[gouldian]

My 2001 "S" and now my 981 "S" scrubbs particularly in reverse and worst when cold as Cliff has said. Some time ago there was a thread where a full technical appraisal was given as to the physics why this happens. It is certainly nothing to worry about but can be disconcerting. I just try and avoid using full lock when possible either in forward or reverse.