One week into ownership of a new 2015 an ongoing issue is raining on my parade. The transmission up shifts brilliantly but when idling it's an absolute horror. Grinding, clunky, whirring; vibrations as if the engine mounts are broken. This is primarily felt when idling and is most pronounced when slowing below 10 mph - the PDK shifting into second and then first. That's when it feels and sounds like a cement mixer. As long as engine speed is above 1000 rpm everything is silky smooth. When starting, as soon as the clutch engages and rpms climb, the PDK settles down and is the perfect transmission.

Countless reviews of the car in the media never made mention of this so I'm assuming that this is not the norm. The service manager however suggested that this being a race car that this clunkiness is may be in the design. Mine being the sole GT3 to land at this dealership precludes a comparison.

I posted on this forum in the hope that other owners would comment on this predicament. I just traded a Turbo S and that transmission was absolutely transparent. I realize that the GT3 gearing is shorter and shift times are optimized, but my around town driveability is horrendous. And yes, it's my daily driver.

 

Firstly, it is normal.
The engine and transmission is most comfortable at slightly higher revs.
My suggestion would be to use the manual mode for lower speeds and keep the refs slightly higher than the auto would. Lugging the engine (which auto does) is just about the worst thing to do. Keep it in manual,and keep the revs up.

 

I never use Auto. I always use manual or PDK-sport.....mostly manual.

 

I have a Turbo S and have put a down payment on a 2015 GT3 and would be going down the same road you are experiencing now ..
All the postings and reviews point out to this in a smaller scale , but if it is seriously annoying you ( coming from a turbo S ) , then it would be a matter of importance to see other readers comments and inputs ..

 

I never use the car in auto mode either. It does make a lot of noises at idle. A lot of chatter is how i can describe it. It sounds just like my 997tt did with the light weight flywheel and stage 3 Sachs clutch. 2nd gear to 1st is not the smoothest transition either. I wouldn't worry too much about it. I think it's normal and inherent in the design.

 

It was in the 2014 GT3 I drove as well. At low speeds, specifically coming to stops and starts it felt like a E60 M5 SMG or Lambo E Gear transmission around town, jerky. I believe its normal for the PDK-S, the car is meant to be driven at speed.

 

I had this discussion on rennlist... The greatest reference is a Lambo e-gear.. At low speeds its like memory lane driving the Gallardo I owned.... clunk clunk etc etc.. However as soon as you start driving it more aggressive the car comes alive and everything syncs perfectly.. The more I drive it I just learn to ignore those qwerks... First week I drove it in manual mode 100% using the gear lever.. Now I drive it in mostly auto mode.. Yea it somewhat drives me crazy how it upshifts at such low rpm and how if you need to accelerate there is a fine line between that and it downshifting 3 gears and at an instant you're riding at 6k rpm..... Its sort of a committing act when you put your foot down.. A few people have said hopefully its just the car learning my driving habits and it will get better the more I drive it.. I have just over 500 miles in the seat... Its a GT3 and I bought it for its track performance capabilities so ultimately all this is irrelevant in the end for me..

 

This is very consistent with my observations as well - also a surprise because I hadn't heard anything about it prior to my dealer warning me just before I drove the car out the door. The advice above to use manual works for me, but it is still annoying.

I don't get the the "auto" mode at all - if I were to second guess the Porsche engineers, which I am, I don't know why they didn't program the "auto" to shift at higher RPMs. I suspect that they are trying to generate better gas mileage by keeping the RPMs low and shifting early - if true, what a bunch of BS via our collective governments.

I would be interested in hearing from someone that better understands this transmission than I about what we are actually hearing - I know that the car has less sound insulation, gears are lighter (?), flywheel is lighter/single mass (?) and both clutches are disengaged at idle which means that the moving parts are free to float and rattle without a slipping clutch taking up the slack in the gear train (?).

 

Thank you so much everyone for the quick, positive, feedback. I was struggling between a Lemon Law candidate but I was hoping that this was 'normal' for the GT3 PDK and it the best compromise that Porsche Engineering could do with a quasi track/street automatic.
As a reward for the good news I'm treating my baby to a Sharkwerks exhaust. For sure this will apply some noise cancelling effect towards cabin sound gremlins.

 

Yeah man, I traded my stumbling C2S in, picked up my GT3, drove away, and almost turned around because I thought it was broken. One very knowledgeable Rennlist member explained the PDK-S as having a combination of less packing for sound deadening and a lighter flywheel. My new procedure, which I think adds to the fun, is to pull the paddles as I approach a stop.

 

That's a great tip - I'll try it out tomorrow. Two paddles = one clutch foot!

 

Is it really as bad as an '04 Gallardo around town? I hated the '04 Gallardo and if the GT3 is similar it would honestly turn me off from ordering one next year.

Thanks.

 

This works great, everything goes quiet and smooth. Now, while at the stop, floor it, and drop the paddles!

 

AP calls that, flooring it and letting go of the paddles, the donut mode.

 

Just got my first pdk car and its clanky too . Have you ever been in a gt-r ? Its way more violent than pdk , so yeah its normal

PS: what do you have to worry about , the car is under warrenty ?