I rebuild my own gearbox a year ago, when my syncros wore out, i retired from work and went on a year tour around uk , but last friday driving down the motorway the 5th gear kept jumping out , i thought it cannot be worn out after only 20,000 miles since rebuild?

i came home to newhaven in 4th gear and took the end cover off to find the nut from the end of the lay shaft had come off, each time i was selecting 5th gear it would stay in gear until i accelerated, this caused the gear to ride up the shaft pushing the gear selector and disengaging the gear

i wonder how many other ducato gearboxs have suffered the same fate

i had to grind a bit off the selector arm to stop it hitting the nut and unscrewing it

i put the nut back on with loctight , center punched the thread, reassembled and all is good

i now waiting for the expensive holiday session to finish and continue my travels