Key Takeaways Federal regulators have opened an investigation into nearly 1.3 million Ford F-150 trucks from model years 2015 to 2017.The National Highway Traffic Safety Administration said consumers have complained that the trucks will suddenly downshift and sometimes lock their rear wheels in the process.

The National Highway Traffic Safety Administration has opened an investigation into 1.3 million Ford Motor trucks due to the potential for an unexpected gear downshift.Ford stock added 2.2% Monday, closing at $10.

Regulators received over 100 consumer complaints about transmission shifting to a lower gear without warning. The investigation affects some Ford F-150s.