Yes, that's the sign we use in SC also.
can you describe that sign?
Here, we use the initialized sign with a "t"
two "T" hands, top over bottom, lightly bump the top and bottom hands together a couple of times.
The similar initialized sign we use for car, but with "C" hands.
I was initially taught that the sign for CAR and TRUCK were similar to "DRIVE", but for truck, the hands farther apart.
However, as I've stated in another posts - communication is the key. Not to argue what is and isn't correct.
Accept what your local Deaf community uses, and don't worry about what others tell you is correct or incorrect.