Overdrive Detent Plunger & Spring Housing 57580, 1st & 2nd, 3rd & 4th & Reverse gears, 3 on a gearbox, also fits STD 4 speed Lagonda gearbox tops, as original.

Often damaged upon dismantling when replacing the detent spring 57583U, as original caps are peened into the housing and are very often seized beyond repair, just hacksaw the housing apart & fit a new cap, housing & spring, becuase

This needs to be adjustable as it stops the gearbox jumping out of gear so may need to be retensioned after driving, generally when the car jumps out of gear, nearly always 3rd but not confined to.

Chemi-Blacked for corrosion resistance