Should I use S gear or D gear on the highway?
2 Answers
On the highway, use D gear for normal driving and S gear for overtaking. The reasons are as follows: 1. D gear is the Drive forward gear. It is suitable for all situations except special road conditions like long downhill slopes, so it is also suitable for highway driving. Moreover, using D gear on the highway has benefits because the transmission control module (TCM) has a set of imprecise reasoning theory strategies. It will optimize the transmission according to the driving conditions of the vehicle, somewhat like the learning function of artificial intelligence. Unlike the stop-and-go conditions in urban areas, highway conditions are better. The vehicle operates more efficiently under these conditions. Therefore, the shifting logic of D gear will also be "smarter" in a sense. 2. Using S gear on the highway consumes more fuel. If you use S gear on the highway, you won't get this effect. Because S gear is the Sport mode, it is another set of shifting logic in the transmission control module (TCM) and does not affect the daily use of D gear. If you want to clean carbon deposits on the highway, you can also use S gear. Because in S gear, when the engine runs at high speed, the throttle opening will be larger, and the intake will be faster, which can remove some carbon deposits that are not firmly attached to the inner wall of the intake pipe.
I've been driving for over twenty years, and on the highway, I mostly use the D gear. It's worry-free and fuel-efficient, with the engine running as smoothly as gliding on ice, perfect for long-distance cruising. When it's time to overtake, temporarily shifting to S gear is quite powerful—quick power response, and you can overtake in just one or two moves. But don't overuse S gear; high RPMs mean higher fuel consumption, and the car can overheat easily. On long trips, you've got to take care of the machine. Sometimes, when stuck in traffic, switching back to D gear is more convenient for maintaining stable speed—safety first. I also like to check the car's condition, like the transmission fluid, as regular maintenance ensures smoother gear shifts.
