Springs & Detents

Detent and selector springs decide how a manual gearbox feels at the lever: how firmly each gear clicks into place and how strongly the lever centres in the gate. Heavy-duty transmission detent springs and heavy-duty gear selector springs are listed here.

Inside the gearbox, spring-loaded balls or plungers press into notches on the selector shafts. They hold each shaft in neutral or in gear and give the click you feel as a gear engages, while selector springs usually centre the lever across the gate. With time and hard use these springs lose force, and the change feels vague or the lever wanders.

Heavy-duty springs press harder, so each position is better defined and the lever returns more positively. The cost is extra shift effort, which adds to the effort of a short shifter.

Points to weigh:

• Detent or selector: detent springs change the click into and out of gear, while selector springs change how the lever centres.
• Gearbox: most titles name the models the springs are for, and spring length and rate are specific to each gearbox design.
• Use: with a short shifter, consider whether the combined effort suits daily driving as well as the track.

On many gearboxes the detent springs sit behind bolts or plugs in the casing, so they can be changed without opening the gearbox. Keep the parts in order as they come out, use new sealing washers and tighten the plugs to the specified torque. Check the oil level afterwards, then run through the gears with the engine off before driving.