How can you tell if your transmission has really been replaced?

To verify if your transmission has been replaced, check for a new transmission identification number on the unit, which should match the paperwork from the installation. Additionally, inspect the condition of the Transmission Fluid; fresh fluid typically indicates a recent replacement. You can also look for any new or clean parts around the transmission area, and if possible, request a mechanic to confirm the installation. Lastly, a test drive can reveal smooth shifting and improved performance, indicating a successful replacement.