Which gear should an automatic transmission car use for high-speed driving?

[VanGeorge]

When driving normally on the highway, it is generally recommended to use the D (Drive) gear for the following reasons: 1. Better fuel economy - continuously using S (Sport) mode consumes more fuel as increased engine power generates excessive heat, which can cause significant damage to the engine. Therefore, D gear should be used for normal driving. 2. When overtaking, you can temporarily switch to S gear to obtain instant stronger power for easier quick overtaking, but remember to shift back to D gear afterward. Although S gear provides faster acceleration, it's not suitable for long-distance driving. Additionally, when climbing long and steep slopes where D gear struggles, switching to S gear provides more sufficient power for more stable climbing and prevents rolling back.