Most of us have wondered what the little button on the gear lever actually does, and honestly asking around Bangladeshi drivers did not get me far as it seems that most people do not use the overdrive option at all.
Using the overdrive gear could actually prolong the engine health of your precious vehicle, especially if you are taking your car on the highway often.
Since the advancement of the engine mechanism and highway transportation, overdrive in automatic cars has come a long way.
In some automatic transmission vehicles, the word "overdrive" refers to the highest gear that can be selected. Practically every car on the road today has at least one overdrive gear in the transmission.
For the engine to run most efficiently, the engine must also run on lower RPMs, thus putting less pressure on the engine. That's when the overdrive gear came into play.
What exactly is an Overdrive Gear?
Overdrive, or OD, is the highest gear in an automatic transmission. On older vehicles, a physical overdrive button or a lever must be pressed manually. When the overdrive button is pressed, the engine runs at low revolutions per minute (RPM).
This will result in reduced noise from the engine while travelling at a constant pace on the highway. It will also make your engine more fuel efficient, allowing you to get the most out of the power you generate.
How to make the most of Overdrive in an automatic car?
Often, cars with this gear have an overdrive button. Turning it on means locking it out, not engaging it. When you push it, the transmission goes through all of the gears and then limits the operation of the remaining gears. When you push the O/D button while driving at high speeds, a downshift from the highest gear occurs.
For normal driving, keep the OD switch turned on at all times. Regardless of your option, your vehicle will automatically change into top gear if necessary. Yet, there are specific circumstances in which shifting into overdrive might increase the car's performance, situations such as:
1. When you accelerate- It's the ideal situation for using the overdrive in an automatic vehicle. When you exceed 100 km/h in your vehicle, the RPM rises and the engine becomes increasingly stressed. Turning on the OD will work like magic to relieve engine pressure and lower the RPM.
Nevertheless, don't use it if you're going less than 80 km/h or if you are driving in a city because the speed is inconsistent.
Only when used correctly will the OD extend the life of your car's engine and drivetrain.
2. When it's time to downshift- When you're driving downhill or caught in a long traffic congestion, your braking system has to take a beating. Also, going down a steep road demands constant pressure on the brake pedal, whereas driving through heavy traffic involves rapid pedal presses and increased speed. When used in these scenarios, the OD will keep the RPM above idle without stressing the brake or the engine.
What are the consequences of improper O/D gear use?
Turning on overdrive in an automatic car allows you to use the entire transmission range. It also aids in the optimization of transmission life and the increase of fuel efficiency.
However, if used inappropriately, such as when towing, travelling uphill, or going slower than 80mph, it will cause irreversible harm. It will quickly burn out the transmission, which is an expensive repair that would cost well above six figures to repair and reinstall.
I also recommend you to take suggestions practically from someone who knows how to use the OD gear properly.
There are currently hundreds of videos on YouTube where you can have an idea of how to use it as well.
