From one of the links WWDiesel posted earlier:
NHTSA wrote:
Some 2004-2007 MY Jeep Liberty vehicles, not included in recall L27 (NHTSA 12V-085), may have been built with rear lower control arms that can experience excessive corrosion. The rear lower control arms may experience excessive corrosion, eventually resulting in a fracture.
The suspect period began at Toledo North Assembly Plant on April 29, 2003, when 2004 MY production began with a new rear lower control arm design which resulted in insufficient water management and reduced corrosion protection, to June 29, 2007, when production ended.
Similar vehicles not included in the recall were built with the 2002-2003 MY rear lower control arm, which is of a different design.
source:
https://static.nhtsa.gov/odi/rcl/2018/RCLRPT-18V278-6812.pdfThe 2005 and 2006 parts catalog originally listed the rear lower control arms as 52128866AA. Plugging this part number
into a Mopar parts site shows this part is still available, and does not show the part as being superseded. This goes with what idparts says:
idparts wrote:
The recall involved replacing the rear control arms, but, with the SAME DESIGNED PART. The the replacement part still suffers from the same problem where the sway bar bracket rusts off! All the recall did was literally push the problem down the road a few years until the truck was old enough it wasn't Jeep's liability.
Also they have a good picture comparing the OEM design to the Moog (aftermarket) design:
https://www.idparts.com/jeep-liberty-crd-rear-lower-control-arm-52128866aa-moog-ck641180-p-6146.html