The manual trans. has a gate for reverse that would reduce the chance of inadvertently putting in it reverse, the pdk not so much.

 

No, just pull both paddles and it drops to neutral.

And there is no wear on brake pads & rotors when stopped.

But ultimately, putting PDK in neutral when stopped at a light has no benefit, or detriment, but probably means he either has a nervous tick or has the neurotic habit of revving the motor before flicking it into D or 1st when the light changes.

 

+3 now...though seriously. The added, needless use/wear of the shifter, though absolutely miniscule and beneath consideration, is actually roughly equivalent to the amount of "reduced strain/pressure on the gearbox" that he's thinking about...with a slushbox automatic. When a conventional torque-converter-equipped automatic is sitting at a stop while in Drive, there is a small amount of hydraulic drag in the torque converter that uses a bit of extra fuel (to maintain rpm while overcoming that drag) vs what it would use if it was in Neutral...and the same is true of the small amount of extra heat generated in the transmission fluid by the hydraulic "slippage" in the converter. While these two considerations (extra fuel burned and extra heat generated) are absolutely present in any slushbox that is stopped in Drive, they were also thoroughly taken into consideration during the design phase of the transmission, so that it is in no way harmful to leave the transmission in drive at a stop.

But all of that is in reference to, and true of, an conventional torque-converter-equipped automatic. The PDK automatic has no torque converter. It's just gears and clutches. When it is sitting at a stop in Drive, even though the transmission has preselected first gear, the drive clutch is disengaged, so there is no extra drag or heat being generated...exactly like a manual transmission that's sitting at a stop in Neutral.

So, either your friend is mistakenly thinking of the older, non-applicable technology of a conventional automatic, or...Some of this might be true, though "Poser" may be the wrong term. It's probably not so much that he wants to appear to have a manual. It's possible that he is simply feeling the need to do something, and is rationalizing that need into 'reducing strain/pressure on the gearbox'. You know him better than we do...

 

What he said... The clutch was already disengaged (which is why creeping works with the standard PDK, because it releases it slowly as you remove your foot from the brakes) so this is just silly, and like any auto, obviously the engineers took all this in to account and expect the car to be left in drive.

 

what is it about "automatic" that he doesn't understand

 

You friend is going to be so embarrassed after reading all these responses

 

Whatever people said above or simply because you don't have to put your foot down on the brakes while waiting for your signal to turn green.
-If you are on a flat surface, you don't need to put your foot down on brakes to prevent it from rolling forward.
-If you are on inclined surface, you can put it in D and just wait for the signal.
-If you are on declined surface, you have to put your foot down on the brakes.

I personally hate putting my foot down on brakes for a long signal light so I know places where I have to idle for awhile. But, I don't do this at every signal light.

(Not a PDK owner, may not be applicable to PDK)

 

My Dad did that all the time in his car (BMW) I always thought it was odd. But he also is a two foot driver. Uses the left foot for braking and he has an automatic and always had one. I guess it's what you're used to. Ever notice when driving with other all the different ways people hold the steering wheel.

 

Whenever I see people who do this, they are usually a long-time manual driver. My guess is that your dad is lying to you!

 

That's just silly.....

 

seems a strange habit no doubt and there's plenty of guesses listed here.
I've done it before in my car (after reading about it here) and find it odd.
why does Porsche enable it to happen when pulling both paddles?
Anyone know why it's programed to do that?

 

I usually shift into N when stopped at the red light, particularly for long stops. My reason being that as the car can crawl forward, it seems to imply that the clutch is partially engaged.

See post #7 here: http://rennlist.com/forums/997-forum...ffic-stop.html

All those who keep the PDK in D - is there any documentation proof that the clutch is fully disengaged when stopped and in D?

 

Uh Ha. That explains a number of things I have questions about then.

 

Heck, engage the auto stop/start feature and save wear and tear on the engine internals and gas to boot, hehehe! That feature is just too creepy for me to use.

But seriously, I like my foot on the brake pedal when stopped at a light, because you never know when some moron is going to rear end you or tap your rear, and your foot on the brake could keep you from doing the same to the guy in front of you.

 

Regarding the the technique of pulling both paddles to engage neutral. What happens when one is rolling downhill on the freeway and engage neutral and then decide to re engage by pulling the plus paddle? What gear does it select.