NAFTA-made vehicles may be nationalized at Laredo and some other ports of entry. Check with a broker as to model years. This is a reputable broker to nationalize your vehicle. There is no way to legally nationalize a vehicle that is already in Mexico. 

A citizen or temporary or permanent resident may nationalize a vehicle. You may import 2016 and 2017. Each November, the year allowed to nationalize increases by one year as those are the two model years that an importer pays a 10% import duty based on the value set by Aduana (Customs). Older vehicles may be nationalized but you pay 50% of the value as established by Aduana. In addition, all vehicles when nationalized, pay a tax of 16%.

For new and used vehicles the first digit of the VIN must start with 1, 2, 3, 4 or 5. The only exception is for classic vehicles, 30 years or older. They can be from any country of origin. The original title is required and it must be clean meaning not flooded, not stolen, not salvaged, etc.

If anyone offers to nationalize a vehicle and the process is to be completed within days, or registration needs to be in the name of a Mexican citizen or process comes with license plates including from Mexico City, the process is illegal. If you want to check out such a process go and ask your local SAT / Aduana office if it is legal. Each car when legally nationalized receives a ‘pedimento’ from Aduana.