Q: Oil drain plug is rounded off on my 2016 Chevy cruze. Can I replace just the drain plug or the whole oil pan

There is no need to replace anything other than the drain plug and that part is sold separately. If, by chance, the internal threads in the oil pan are damaged, those can be restored. For your car, the drain plug is GM part number 55577568. Generic metric size drain plugs (from auto parts stores) will work, too, so long as the plug diameter is 12 mm and the thread pitch is 1.75. Length should be around 17-18 mm. It is easy to remove rounded off drain plugs with professional tools. If the shop had difficulty, they are not using the correct tool. The fact that the plug is damaged means that the wrong tool was used in the past to remove the plug. YourMechanic can change the oil and filter on your car right at your home or office and without needlessly damaging your car. If you desire mobile service, please refer to YourMechanic’s engine oil and filter service request page. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.