Some owners of 2012-2013 Chevy Avalanche or 2012-2014 Silverado may experience a harsh 6-4 downshift. The customer may note that during a heavy throttle application, a tie-up feeling followed after the throttle has been released, by a harsh 6-4 downshift.
Perform the Reset Transmission Adapts in the service manual. Road test to see if the condition has been corrected. If not, this bulletin does not apply.
About the Author
Information courtesy of Mitchell 1
Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.
Mike Mavrigian
Motor Age Editor
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.