In 2020, Fiat Chrysler America recalled 67,248 units of the 2014-2017 Jeep Cherokee in the United States over a transmission issue that could result in a loss of power or rollaway situation. At the time, paperwork filed with the National Highway Traffic Safety Administration explained that certain “vehicles were built with a two speed Power Transfer Unit (“PTU”) that allows relative movement between the differential input splines and the transmission output shaft.” The movement could wear down the input splines, causing a loss of engagement between transmission and differential, thereby cutting power to the front wheels. Worn splines could also prevent the transmission from engaging Park when stationary, leading to a possible rollaway situation. That recall applied only to all-wheel-drive models with the two-speed Power Transfer Unit, which simulates the two-speed transfer case found in many part-time four-wheel-drive trucks and SUVs. Jeep brands the affected systems as “Active Drive II” or “Active Drive Lock.”
Vehicles among the recall population that featured the PTU model in question benefited from “more robust differential splines.” The fix for the recalled vehicles wasn’t replacing the worn PTU splines with the upgraded versions. The fix was a software update that worked around the fault to either alert the driver, to shift power to the rear wheels when the malfunction occurred, or to automatically apply the parking brake if the fault happened while the driver was attempting to shift into park.
What’s stranger is that Jeep has issued a new recall for a subset of the original recall population, addressing the same issue with the same PTU part numbers. This time there are only 25,980 Cherokees involved, only 1% thought to be afflicted with the PTU problem, but it expands on the previous population of 67,248 units. The language in the Safety Recall Reports is identical, only the build dates have changed. The 2020 recall covered SUVs built from April 14, 2014 to October 10, 2016. This new recall covers SUVs built from September 3, 2015 to September 23, 2016.
As before, the fix is software. The new Safety Recall Report copies the 2020 version in saying, “The remedy component will be a software flash that, if failure of the input splines occurs, causes a malfunction indicator lamp to illuminate, rear axle engagement to prevent a loss of motive power, and electronic parking brake activation when the vehicle is in PARK to prevent a loss of PARK function.” Considering the 1% expected affected population, this reads to us like Jeep wants to use software to find the problem vehicles that need a day at the dealer’s, instead of flooding dealer techs with lengthy fishing expeditions into 93,000 Cherokee drivetrains.
Jeep says it will begin mailing notification letters to owners on June 16. Until then, owners can contact the FCA customer service at 800-853-1403 and mention internal recall 45A; the previous recall was W47. Owners may also contact the NHTSA’s Vehicle Safety Hotline at 888-327-4236 (TTY 800-424-9153), or go to www.nhtsa.gov, and refer to campaign number 23V-302.
Read the full article here