Skipping gears: Mastering manual transmission without risks
Manual gearboxes offer full control over gear selection at any moment, allowing the driver to skip gears, unlike automatics. However, is this driving method beneficial for the drivetrain?
Despite the increasing popularity of automatic gearboxes, cars with manual transmissions still dominate on the roads. Changing gears is routine for many drivers and doesn't require much thought.
Few people, however, contemplate whether skipping a gear is a mistake. The answer is: it depends on how it's done. The crucial element is the method used to change the gears. Different "traps" can occur during acceleration compared to downshifting.
Skipping gears when shifting to higher gears
Many drivers skip gears, and eco-driving instructors even recommend it. The benefits are clear—higher gears reduce engine speed, lowering fuel consumption. The key is to maintain an optimal engine speed.
Consider this scenario: a driver wants to quickly reach a higher speed. Driving in second gear, they increase the revs and then immediately shift into fourth gear, skipping third. This process is smoother and quicker than switching sequentially, but is it safe for the vehicle?
It can be safe as long as the engine speed after changing gear doesn't drop too low. For instance, you accelerate to 37 mph in second gear at 4000 rpm. After shifting to fourth gear, the revs drop to 2000 rpm, typically allowing for further acceleration or maintaining a steady speed.
However, if you switch directly from second to fifth gear, the revs might drop below 1500 rpm, which could strain the drivetrain and engine. What about the reverse situation?
Skipping gears when shifting to lower gears
Is it feasible to skip gears when downshifting? Some drivers, especially in cars with petrol engines, do this, for example, just before overtaking. Driving at 50 mph in fifth gear, the engine runs at 2000 rpm. Changing to third gear will raise the revs above 3000 rpm, allowing for more efficient manoeuvres.
However, it's important to remember that a sudden increase in revs can be more harmful than a decrease. A sharp downshift places a lot of stress on the drivetrain and risks locking the wheels on a slippery surface. Experienced drivers prepare for the downshift by raising the engine revs with a gentle press of the accelerator, which mitigates the potential effects of a harsh gear change. Further materials can provide more about the so-called heel-and-toe technique.
Proper revs are crucial
So, is skipping gears in manual gearboxes possible? Yes, but one must control the engine speed. The optimal value varies for each car and requires some intuition. Skipping to higher gears is less risky and is often practised.
Reducing multiple gears at once is a more advanced skill. Given the potential risk of slipping and the forces exerted on the drivetrain, it is not a technique recommended for everyday driving.