Opel Movano B will not select gears above third

A sudden inability to select the higher gears while the lower gears still work is serious, but it does not always mean that the gearbox is beyond repair. Distinguish between two situations before deciding on a rebuild. If the gears cannot be selected but the gear lever moves freely and feels vague, the gear-change mechanism is usually responsible: a worn gear selector or stretched gearshift cables. This is an inexpensive repair performed without removing the gearbox. If the lever meets solid resistance and a grinding noise is heard during an attempted change, the damage is internal.

What damages the Movano B gearbox, and how can it be prevented?

Owner reports mention first failures at around 70,000 km, with the problem typically appearing between 100,000 and 160,000 km, much more often in vehicles towing trailers or operating fully laden. Neglected gearbox oil is the main cause. The manufacturer specifies no fixed interval, so many examples have never had it changed. Worn gearbox shaft bearings shed metal particles, which contaminate the oil and accelerate wear of further components until the synchronisers seize. Prevention is simple and inexpensive: change the gearbox oil approximately every 100,000 km. An increasing whine in higher gears is the first warning sign and must not be ignored. At that stage, replacing the full bearing set is sufficient; later, the entire gearbox will require rebuilding. If the clutch does not disengage cleanly, inspect it as well, because a worn clutch plate or concentric clutch slave cylinder with release bearing can produce symptoms deceptively similar to gearbox damage.