Preselector Gearbox - Advantages of Preselector Gearboxes

Advantages of Preselector Gearboxes

For the driver, there are two advantages:

• Fast shifting, with only a single operation. This requires less skill to learn than techniques like double declutching and it offers faster shifts when racing.
• Ability to handle far more engine power, with a lighter mechanism.

In engineering terms, some designs of pre-selector gearbox may offer particular advantages. The Wilson gearbox offers these, although they're also shared by some of the other designs, even though the designs are quite different:

• Their friction components are brakes, rather than clutches. These are simpler to engineer, as the wear components can be arranged to not also be rotating parts.
• The friction wear components can be mounted on the outside of the mechanism, rather than buried within it. This makes maintenance and regular adjustment easier.

They were common on Daimler cars and commercial vehicles, Maybach, Alvis, Talbot-Lago, and Armstrong Siddeley cars as well as on many London buses. They have also been used in racing cars, such as the 1935 ERA R4D, and hillclimbing cars such as Auto Union "Silver Arrows". Military applications began in 1929 included tanks such as the German Tiger I and Tiger II in World War II, through to the current tanks such as Challenger 2.