Have you ever wondered how you are able to change gears so effortlessly when you drive down the road? You simply depress the clutch and move the gear stick into the appropriate slot so that the car can accelerate at an appropriate speed towards its destination. Much of the work is performed by a set of different gears contained within the box itself, but the real magic happens due to a special mechanism known as a synchromesh. What is this and what should you do if you begin to encounter any problems?

Gear Selection

Within the gearbox are a number of individual gears that have varying diameters. These will all need to be engaged at different times as and when selected by the driver, and they are all equipped with a set of teeth that must align with the primary shaft for the perfect selection.

Making It Easy

However, this will certainly rely on perfect alignment and the gears will need to be spinning at the same speeds, or those teeth could grind together and would quickly fail. The driver could do this manually by paying very close attention to the engine's revolutions and by double-declutching the pedal, but this is hard work at the best of times and is why the synchromesh system was invented.

How It Works

Without a doubt, this invention was groundbreaking, and it has revolutionised the task of everyday driving. It's quite a complex scenario to explain but it will basically rely on an additional ring and a synchromesh clutch. This clutch mechanism is able to spin independently and helps to align the gears at the perfect moment when both are spinning at the same time. In other words, it will quickly isolate and then regulate the speed of each gear as the driver selects the changing fork, and as pressure is increased, it will then allow both gears to come together as one.

Signs of a Problem

There are many separate parts involved and a tremendous amount of heat and friction to deal with, so it's not surprising that, from time to time, parts of the synchromesh unit can begin to fail. In this case, the driver will find it hard to change gears properly and may hear a grinding or crunching noise on each occasion. When this happens, it's important to take action to reduce the amount of damages, but it is equally as important to bring in an experienced technician to conduct the repairs.

For more information on gearbox repairs, contact a mechanic.

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