Some 2020-2022 Explorer/Aviator/Police Interceptor Utility vehicles may exhibit erratic transfer case operation and/or noise. This may be due to water intrusion between the transmission and the transfer case. The transfer case installation procedure has been updated in Workshop Manual (WSM), Section 307-07B to prevent this concern from reoccurring. Follow the updated WSM procedure to make sure the top of the transfer case is sealed upon installation.