What 51 owners told NHTSA about the 2011 Porsche Cayenne S

I HAVE HAD THE TRANSFER CASE REPLACED IN THIS VEHICLE TWICE IN THE LAST 25K MILES. AT 65K MILES THE CAR IS DOING THE FAMILIAR GRINDING AND SURGING AGAIN, EVIDENT IT WILL NEED A THIRD $5-6000 TRANSFER CASE. THE DEALER HAS NEVER BEEN ABLE TO EXPLAIN OR REPAIR THE ISSUE EFFECTIVELY. THE MANUFACTURER DOES NOT REPLY TO INQUIRIES, IT IS MY REQUEST THAT THEY BE FORCED TO PROVIDE A PERMANENT, RELIABLE FIX FOR THIS ISSUE. I'M WORRIED THIS COULD CAUSE A SAFETY ISSUE UNDER THE RIGHT CIRCUMSTANCE SINCE IT HAPPENS WHILE THE CAR IS IN MOTION. THE MECHANICS AT THE VARIOUS DEALERS HAVE TOLD ME ITS A WELL KNOWN ISSUE SPANNING PORSCHE SUVS FROM 2008 THROUGH THE PRESENT. GOTTA WONDER WHAT THIS MANUFACTURER IS THINKING HERE AND WHY THEY ARE HIDING THE DETAILS.

NHTSA ODI 11180247

THE FACTORY PROGRAMMING OF THE COMPUTER AND SPEED CONTROL IS INCORRECT. PORSCHE STATES THAT THE VEHICLE IS OPERATING WITHIN CHARACTERISTICS AND SPECIFICATIONS [AND ACCORDING TO US LAW A VARIANCE OF UP TO 18% IS ALLOWED IN THE SPEEDOMETER.] HOWEVER, PORSCHE HAS TAKEN THE US LAW TO MEAN THAT IT IS ALLOWED TO INTENTIONALLY PROGRAM ITS COMPUTERS TO THE SAME SPECIFICATIONS AS ANALOG GAUGES. PORSCHE CANNOT DEMONSTRATE THAT THE INACCURACY IN THE SPEEDOMETER IS NOT EFFECTING THE HYBRID OPERATIONS OF THE VEHICLE. THE INACCURATE SPEED READING MAY ALSO CREATE INACCURATE ODOMETER READINGS. IN ADDITION THE VEHICLE HAS PROBLEMS WITH HARD BRAKING WHICH IS ESPECIALLY PRONOUNCED WHEN THE VEHICLE IS UNDER CRUISE CONTROL. AND IN CERTAIN INSTANCES THERE IS LAG ON ACCELERATION. PORSCHE HAS REFUSED TO REPROGRAM THE SPEEDOMETER CONTROLS TO ACTUAL SPEED. GIVEN THAT THE ONLY PROBLEMS ON THE VEHICLE ARE RELATED TO THE SPEED OF THE VEHICLE, IT SEEMS THAT PORSCHE SHOULD BE CAPABLE OF PROVIDING A SOLUTION BY REPROGRAMMING THE ONBOARD COMPUTERS. *TT

NHTSA ODI 10425928