The GTI's 6-speed manual (the 02Q on Mk5-onward, the earlier 02M/02J on Mk4-era cars) is a tough, long-lived box, but it has its own wear items — synchros, bearings, and shift feel — that owners meet as the car ages. Most "gearbox problems" on a manual GTI are actually the clutch, shifter linkage, or fluid, not the gears, so diagnose before you fear a rebuild
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