Chrysler Group said it had "resolved" differences with the National Highway Traffic Safety Administration (NHTSA) over NHTSA's request to recall 1993-2004 Jeep Grand Cherokee and 2002-07 Jeep Liberty [exported as Cherokee] vehicles and would now conduct a voluntary campaign that, in addition to a visual inspection of the vehicle will, if necessary, provide an upgrade to the rear structure of the vehicle to better manage crash forces in low-speed impacts.