what is skip shift

Manual Transmission Shift Inhibitors

Certain manual transmissions incorporate a mechanism designed to encourage fuel-efficient driving by prompting the driver to bypass specific gears during upshifts. This system's primary function is to reduce engine revolutions per minute (RPM) during acceleration, thereby conserving fuel. It is most commonly found in vehicles designed for optimal fuel economy.

System Operation

The system typically functions by employing an internal gate or an electronic control that prevents direct shifting from a lower gear to a gear immediately adjacent in the sequence. Instead, it encourages the driver to "skip" a gear, for example, shifting directly from 1st gear to 3rd gear or from 2nd gear to 4th gear. Activation is usually dependent on specific parameters such as vehicle speed, engine load, and throttle position. The presence of a shift indicator light on the instrument panel often signals the driver when the system is active and recommends the gear to which the driver should shift.

Mechanical Implementation

In mechanically implemented versions, the gearshift lever's movement may be physically restricted by an internal mechanism within the transmission. This restriction is often bypassed if the driver applies sufficient force or if the operating conditions are not conducive to fuel-efficient driving (e.g., during aggressive acceleration).

Electronic Control Implementation

Electronically controlled implementations rely on sensors and a control module to determine when conditions are suitable for gear skipping. The module can then activate a solenoid or similar device to create a physical or perceived barrier to prevent the driver from selecting the adjacent gear. These systems are generally more sophisticated and can adapt to different driving styles.

Benefits

  • Improved Fuel Efficiency: By reducing engine RPM, the system minimizes fuel consumption, especially during moderate acceleration.
  • Reduced Emissions: Lower engine RPM contributes to a reduction in exhaust emissions.

Drawbacks

  • Reduced Performance Feel: Some drivers may find the system intrusive and detract from the overall driving experience.
  • Potential for Driver Confusion: The system can cause confusion or hesitation, particularly for drivers unfamiliar with its operation.
  • Possible Gearbox Damage (Rare): Incorrectly forcing a shift against the system's resistance can, in rare cases, potentially lead to premature wear or damage to the transmission components.