Loose CATs Rattle Cadillacs
Owners of 2014-2015 Cadillac CTS sedans, XTS or ATS vehicles equipped with a 3.6L twin turbo engine might comment on a brief rattle or tick when revving the engine when the transmission is in park or neutral.
Note location of bracket to transmission fasteners.
The same rattle or tick can sometimes be heard at the beginning or end of a vehicle acceleration while in drive. This might be due to the turbocharger wastegate. The condition might be caused by loose converter bracket nuts or might be a normal characteristic of the turbo wastegate.Inspect the M8 nuts that secure the catalytic converters to the exhaust bracket. If the nuts are loose, replace them with new torque-prevailing nuts, P/N 11546441.
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 MavrigianMike 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.
