Engaging a lower gear at high speed and finding out what happens is something that most curious people among us would have contemplated at least once in their lives. Doing this on a motorcycle that isn’t equipped with a slipper clutch will surely lock the rear wheel, causing a big skid, or worse, the engine and gearbox may grenade on you. But what happens when a similar stunt is pulled off on a car – a Maruti Baleno to be specific? Well, Arun Panwar who runs his own Youtube channel decided to demonstrate this to us so that we don’t have to try similar things on our cars. Check out the video below to watch how it all panned out.
As the video indicates, the vlogger accelerates the Maruti Baleno to about 50 Kmph, and tries to slot the car into reverse. There’s a grinding noise that’s heard, with the gear shifter showing some resistance, and finally, reverse gear is not engaged. The vlogger then attempts the same stunt at higher and lower speeds, with the same result. So, if you’re wondering why this happens, it’s by design actually. Engineers of modern day cars engineer built-in fail safe mechanisms to ensure passenger safety and longevity of car parts. One such fail safe mechanism is that of not allowing the car’s reverse gear to be engaged inadvertently.
It’s easy to miss slotting the 4th gear from 5th gear while slowing down, and instead move directly to the reverse gear. This is a mistake that most new drivers make. To ensure that a driver abruptly does not slot the gearbox into reverse in a moving car, engineers have designed the syncromesh mechanism of the gearbox to not engage when someone tries to slot it into reverse when the car is moving. So, to engage reverse gear, the car has to come to a total halt. This mechanism also ensures better gearbox life. If the gearbox were to allow a driver to slot the car into reverse at high speed, it could not just result in a crash due to the wheels locking but also could damage the transmission leaving the vehicle stranded.
This fail safe mechanism is smoother on automatic cars, where the gear shifting is controlled by a computer/micro chip. In case of automatic cars, shifting to reverse gear at high speed will produce no response. The automatic gear shifter will move to the reverse gear position but will not engage reverse gear. Here is a video that shows what exactly happens when you shift an automatic car to reverse gear at high (any) speed.