Aug 2 (Reuters) - The National Highway Traffic Safety Administration on Friday upgraded its investigation into nearly 1 million Stellantis' Dodge brand vehicles to an engineering analysis from a preliminary evaluation over faulty door locks and windows.

The analysis involves certain Dodge Journey crossovers built between 2009 and 2020.

(Reporting by Nathan Gomes in Bengaluru; Editing by Nivedita Bhattacharjee)