Valvoline Instant Oil Change

I own a 2015 Jeep Grand Cherokee with approximately 140,000 miles. On December 11, 2023, I brought the vehicle in for routine maintenance at Valvoline Instant Oil Change in Milford, CT. The service included rear and front differential fluid changes, gearbox treatment, and power steering fluid replacement. Shortly after this service was completed, a new issue appeared immediately that had not existed before. A “Service 4x4 System” warning came on the dashboard. This warning did not clear after driving, even though I was advised it might reset after some mileage. The issue remained persistent. From that point on, the vehicle continued to show the same AWD/4x4 system warning. In addition, I began experiencing intermittent loss of some electronic functions, including cruise control, which still does not work. To diagnose the issue, I initially suspected the rear differential actuator motor. I purchased an OEM-style replacement axle motor kit (Part Number 68214628AA). The part was installed at a repair shop, but it did not resolve the issue. the “Service 4x4 System” warning remained unchanged. After that, a transmission module was replaced and programmed, but this also did not fix the problem. At this point, the vehicle still has the same persistent “Service 4x4 System” warning and intermittent cruise control malfunction. Despite replacing or testing both the rear differential actuator motor and the transmission module, the issue has not been resolved. The problem clearly began immediately after the rear differential fluid service and has remained unresolved since then, despite multiple repair attempts.

Very helpful and professional