In a letter received on October 24, 2018, a citizen petitioned the National Highway Traffic Safety Administration (NHTSA) to initiate a safety defect investigation into frame weld deficiencies on model year (MY) 2018 'JL' Jeep Wrangler vehicles. The petitioner described a broad list of frame weld deficiencies, including porous welds, excessive slag, lack of weld penetration, over penetration of welds, overweld or weld drip, and weld splash. The weld defects are allegedly located at a variety of locations on the frame assembly.On November 16, 2018, the Office of Defects Investigation (ODI) opened a Defect Petition (DP18-004) to evaluate whether to grant or deny the petition. On March 8, 2019, ODI sent an Information Request letter to Fiat Chrysler Automobiles (FCA) requesting information on frame weld related issues on all MY 2018-2019 Jeep Wrangler 'JL' vehicles. Due to a previous steering related recall that was caused by a misaligned weld on the front track bar (NHTSA Recall No. 18V-675), ODI opted to include a request for additional information concerning reports of steering shimmy or wobble, loose steering, and steering lockup in the March request letter. ODI has performed a preliminary analysis on the information obtained from FCA. Based on ODI's review of the applicable materials, NHTSA has decided to grant the petition. While reviewing the applicable materials obtained from the manufacturer, ODI identified various reports and references to frame welded component detachments that were outside of the scope of NHTSA Recall No. 18V-675. Additionally, the information that FCA provided did not adequately address whether frame weld quality deficiencies compromise the structural integrity of vehicles, and therefore may pose an unreasonable risk to motor vehicle safety. Finally, ODI needs to further evaluate the alleged steering-related defects reported through MY 2019 and the alleged defects' relation to weld quality.The petition was granted on September 16, 2019. Preliminary Evaluation PE19-012 has been opened to further assess the scope, frequency, and potential safety-related consequences of alleged weld quality deficiencies and steering related concerns on the MY 2018-2019 'JL' Jeep Wrangler vehicles.The ODI reports cited above can be viewed on NHTSA.gov under the following reference numbers:11234967, 11222390, 11219370, 11217080, 1204905, 11179954, 11171786, 11161243, 11155523, 11153044, 11143617, 11142722, 11142426, 11141336, 11141035, 11140637, 11140344, 11140262, 11140085, 11140057, 11139880, 11139866, 11139557, 11139467, 11139436, 11138974, 11138758, 11138757, 11132030, 11129738, 11129667, 11124312, 11120232, 11119676, 11119650, 11119454, 11119450, 11115658, 11115137, 11113029, 11112515, 11110583, 11109903, 11093172, 11088501, 11076098
