Buying a used gearbox: checks before you order

A used gearbox is not automatically safe or unsafe. The sensible question is whether the exact unit has been identified correctly, whether its condition evidence is credible, and whether the full fitted cost and written terms suit the risk you are taking.

Confirm identity first. Record the complete code and part number from the original unit, then provide the registration and VIN or build details requested by the supplier. The same model description can cover different ratios, casings, electronics or control requirements. A claimed supersession should be supported by current catalogue information for the specific vehicle.

Ask what the evidence proves. Donor mileage and service information can add context, but neither proves remaining life. Ask whether the gearbox was road-tested, bench-tested, inspected after removal or only sold as removed. Obtain current photographs, donor details the seller can lawfully provide, and a written description of known faults and included components.

Plan the installation with a competent repairer. Fluids, filters, seals, clutch or flywheel components, coding and adaptation requirements differ by vehicle and gearbox. Follow the vehicle and component manufacturers' current instructions. Diagnose the original failure before fitting so that an external fault is not carried into the replacement unit.

Compare the contract as well as the price. Check delivery, return carriage, fitting-evidence requirements, excluded labour, voluntary warranty and the seller's process if the unit is misdescribed. Statutory rights may apply when a consumer buys from a trader, but the outcome depends on the contract and facts. Keep the listing, invoice, test evidence and correspondence.

No inspection can guarantee the remaining life of a used part. Confirm identity, condition evidence, fitting requirements and written supplier terms for the individual item.