Gear stick slipping out?

could be seized cables,you don`t say if your gear stick is moving at all,also if it feels very vague and can`t find any gear at all there is a roll pin in the selector mechanism on top of the g/box which are bad for shearing,you can`t buy the roll pin individually and have to take the whole selector mechanism which is very expensive so a scrappy would be worth a go or if you have any engineers living locally they may have roll pins at hand,also have had the breather pipe on top of the g/box interfering with gear selection but it doesn`t sound as if that is your problem and lastly it may be an internal g/box problem which may need a reconditioned or 2nd hand replacement,good luck.

cdc
July 2014