One problem related to transmission slip out of gear has been reported for the 2011 Buick Regal. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2011 Buick Regal based on all problems reported for the 2011 Regal.
Vehicle had 45000 mile's when I bought it in oct 2017 and now has 47500 miles. Car had no problems and drove and looks like new. Last week (09/07/18) it started bucking going down road at @30mph, then would jump into gears at stop. Then did not want to go into reverse. Would not shift out in forward gears. Manual would not work either. We were stuck in traffic at busy intersection. . . All in about 10 minutes time. Limped to aamco transmissions and left it. . . Diagnosis was needed to rebuild transmission. . Cost;3400. 00 have read this has happened on other 2011 models. Should have been a recall. . 45000 miles is still like new and this should have and could have been avoided. . I was lucky to have not been in an accident. Was just driving normal in city when happened.