One problem related to oil pump has been reported for the 2009 GMC Acadia. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 GMC Acadia based on all problems reported for the 2009 Acadia.
While driving the vehicle at 45mph I received a low oil pressure shut off engine. Oil was fine so we took it to have the oil changed. Light came back on. There are no codes being stored in the system. Everyone is guessing what could be wrong with it from a bad oil pump or the pan needs to be cleaned. There is a forum a bunch of other people having the same problem and spending thousands and getting nowhere. Some have had to have a whole new engine installed. Gm says there are no bulletins and they will give me a 100 $ for the vehicle to be serviced by a tech. Just to be checked is 250 $ not including any fixes for the issue.