2018 and 2019 Wrangler models are affected.
For starters, this issue isn't new as it dates back to almost a year ago when a citizen petitioned an investigation to NHTSA on October 24, 2018. The complaints cover weld deficiencies, including porous welds, excessive slag, lack of weld penetration, over penetration of welds, overweld or weld drip, and weld splash, that could affect the structural integrity of the off-roader. By that time, the Office of Defects Investigation (ODI) needed to further evaluate the issue if it warranted the requested investigation.
Gallery: 2018 Jeep Wrangler Rubicon: Review
This month, however, ODI granted the petition and opened the investigation. Earlier this year, ODI sent an Information Request to FCA regarding the issue at hand. This is line with the previous recall on a misaligned weld on the front track bar on Jeep Wranglers, which has caused steering wobbles among affected Wrangler units. It could also be related to the "death wobble" that has been reported before, which led to a class-action lawsuit against FCA.
With the information gathered involving the parties, ODI granted the petition and consequently started the investigation, dated September 17, 2019.
Just to be clear, the Wrangler weld issues aren't related to the recall imposed upon its pickup truck counterpart, the Jeep Gladiator. The returning icon was recalled this week over a possible fracture of the rear axle driveshaft, affecting 3,427 Gladiators, which caused a stop-sale directive on the pickup truck.
Going back to the Wrangler, an estimate of 270,000 units of the off-roader are included in the investigation, covering MY 2018-2019 Jeep Wrangler JL vehicles.