Which Gear is More Fuel-Efficient on the Highway, D or M?

[OJustin]

Using D gear on the highway is more fuel-efficient than M gear. The D gear in an automatic transmission is the forward driving gear, while the M gear is the manual shifting mode of the transmission. When the vehicle is in M gear, it operates similarly to a manual transmission, allowing the driver to manually shift gears based on engine speed and vehicle speed. Here are the details about D and M gears: 1. D gear, also known as the drive gear, activates the corresponding forward gear oil circuit automatically based on throttle opening signals and vehicle speed signals when the gear shift lever is in this position. 2. M gear refers to a gear in cars with a manual-automatic transmission. This means the car can shift gears automatically or manually. By moving the gear lever to the middle of the M+ and M- symbols, pushing the lever towards M+ upshifts one gear, and pushing it towards M- downshifts one gear.