What is the correct way to use D+ and D- in automatic transmission?
2 Answers
Here is the correct way to use D+ and D-: 1. When going downhill, you can shift up to D2 or D3 using "D+": When going downhill, you can shift up to D2 or D3 using "D+". Downhill driving requires the engine braking effect, and gears 2/3 can meet the power demand without needing the high torque of 1st gear. Sometimes, when climbing uphill with sufficient power, you should also use "D+" to upshift to prevent power waste and damage to the engine and transmission. 2. Use "D-" to downshift when going uphill: Uphill driving requires greater power, so you should use "D-" to downshift the vehicle and obtain higher torque for climbing. Similarly, if you encounter a situation where the vehicle is accelerating too quickly downhill, you should also use "D-" to downshift and control the speed. In addition, "D-" can also be used for short-term overtaking or in congested road conditions.
I've been driving automatic transmission cars for over a decade, and I find that proper use of D+ and D- makes driving much smoother. After switching to manual mode, D+ is for upshifting—usually press it once when the speed is stable and the RPM goes up, making gear shifts smoother. D- is used for downshifting, giving an immediate power boost when climbing steep hills or overtaking. In city traffic, downshifting helps with quicker starts, and it also helps control speed when going up or down mountains, reducing brake wear. Avoid downshifting at high RPMs, as it could damage the engine. Manual mode is safer in rain or snow—downshifting early for deceleration provides more stability. Beginners should practice a few times on empty roads; once you get the hang of it, driving an automatic becomes much more flexible. Overall, this feature makes ordinary driving smarter and can even save some fuel.