There's no guarantee that automatic transmissions for Acura cars for sale online are reliable, and a driver should exercise caution before purchasing a transmission he can't test. Rebuilt and remanufactured transmissions are more likely to be reliable.
Manual transmission parts are generally easier to investigate, since individual components can be separated and photographed easily; automatic transmissions are generally sold as self-contained units. Before purchasing a used transmission online, a prospective buyer should ask why it is being sold; most drivers keep their transmissions until they are not worth repairing. In addition, a used transmission that comes with a guarantee, which are more common on rebuilt and remanufactured transmissions, is usually a safer bet.