CVT, DSG and DCT: How Many Ways Can You Say Transmission?
CVT = continuously variable transmission.
DSG = direct shift gearbox
DCT = dual clutch transmission
7G-DCT = basically a dual clutch transmission with a three pointed star
PDK = Doppelkupplung. (double clutch) Porsche’s name for a DCT. (I love this one.)
The first transmission is an automatic transmission, but there are no gears as such. It is constantly changing ratios so that the engine can stay at the peak of its torque curve. This yields better mileage, and this has been validated by both Nissan and Honda switching over their mass market cars to this transmission. They also need to do it to get the better mileage as that mandatory 54.5 miles per gallon rule is staring them right in the face.
The other transmissions are all basically dual clutch transmissions. This means that there are two clutches working, one engaged and the other available to be engaged when you, (or the electronic brain if you are in automatic mode), wants to either upshift or downshift. Part of the economy comes from the transmission being able to shift in an inhuman 60 milliseconds. You heard that right, 60 THOUSANDTHS of a second! Those who like to engage in stoplight drag races also kind of like that feature.
Why do I want to talk about a dual clutch transmission in an article about Hyundai? Well, I just read a horrifying story on a Hyundai forum site that amazed met. It seems that this guy has had a Hyundai Santa Fe which, under normal driving conditions will just. shut. down. The transmission that is. He pulled out of a parking lot, floored it and it seemed to him that the clutches, (as in both of them), just disengaged. It left him with his foot down, the engine roaring, and the car not moving. In traffic. So far the dealer, according to him, hasn’t seemed too interested in getting this resolved. As far as I understand, they’ve made two failed attempts, so I guess that gives them an E for effort. Better than an F, worse than a D.
Is this a common problem? I don’t know, but I have a 2011 VW Sportwagen with 130,000 miles on the clock that has a DSG, and it has never malfunctioned. My son has a 2010 VW Sportwagen with 165,000 miles completed and he has never had a problem either. Quite frankly, I have never heard of this happening to anyone I have ever met with a dual clutch transmission in their car.
I would hope that Hyundai would take this issue very seriously and investigate whether this is a common problem, or just a problem with this one transmission. Get it fixed. If it is a common problem, then it needs to be re-engineered, all the cars with it recalled, and they need to be replaced. Defects like this, if in more than one car, can just wreck a manufacturer’s reputation. Ask General Motors about their ignition switch. Those law suits outlasted a corporate bankruptcy.
My advice? Do it like Tesla does it. Whenever they have a life-threatening problem, or a situation where a life was actually lost, they treat it like an all-alarms fire. They pull out all the stops. They don’t call in the actuaries to determine if it would be cheaper to pay off the claims or fix the problem. They just fix the problem. Like the fire they had a year or two back with a battery pack after someone drove into a steel spike that penetrated the battery pack. They re-engineered the battery pack by adding a titanium shield below the pack, tested it with some real-world cars, found it satisfactory and then deployed it throughout the fleet.
That’s the way you do it. Don’t let the dealer deal with it. You, the manufacturer, deal with it. It’s the right thing to do.
Update: This thread on the Hyundai forums was first posted on 2/9/16, and is still going strong. C’mon Hyundai, give the man a new tranny!