On December 12, 2019, NHTSA's Office of Defects Investigation (ODI) opened Preliminary Evaluation (PE) 19-017 after receiving three Vehicle Owner Questionnaire (VOQ) reports alleging failures of the front driveshaft and/or transfer case, resulting in conditions of 1) a loss of engine power, 2) loss of steering assist, 3) loss of foundation brakes, 4) unintended air bag deployment and 5) engine/cab fires from combustible fluids striking hot exhaust components.?The VOQs involved model year (MY) 2015 through 2017 RAM 4500 and 5500 vehicles. ODI received information from the vehicle manufacturer [Fiat Chrysler Automobiles (FCA)] via information request letters dated February 28, 2020, and April 21,2020.?Supplemental information was received on March 17, 2021. A review of the responsive manufacturer information, and related meetings and presentations, showed that the transfer case failures in 97.5% of the claims did not disable the vehicle. Since analysis showed that a failed driveshaft could result in catastrophic damage to the transfer case as well as other safety risks (i.e. steering/brake failures etc.), ODI shifted the investigation to focus only on the front driveshaft failures.?The double cardan universal joint design requires maintenance lubrication within every 8000 miles.?Despite an under-hood maintenance reminder label and professional servicing at both dealers and independent repair facilities, the driveshafts were often found to be unlubricated due to lack of awareness, difficulty of the operation or the lack of the special tools needed to perform the work.?To increase the maintenance lubrication rates, in the summer of 2021, FCA launched a communications campaign, circulating awareness bulletins, training information, special tool options and instructional videos through more than a dozen channels covering both dealer and independent repair facilities.?Additionally, in the fall of 2021, FCA mailed a VIN-specific letter to each registered owner reminding them of the maintenance needs, and also sent a special grease gun adapter to every FCA US dealer and fleet operator with an FCA US dealer code. Since January 2022, NHTSA has not received a complaint of front driveshaft failure due to lack of lubrication that can lead to failure conditions such as loss of engine power, loss of steering assist, loss of foundation brakes, unintended air bag deployment and engine/cab fires. This drop in complaints, the communications campaign launched by the manufacturer, and the absence of reports from the manufacturer, support the closing of this Preliminary Evaluation. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The Agency reserves the right to take additional action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.
