Good point. They have agreed to a 2nd oil change ( I will definitely watch) and then do my own changes after this (Mobil 1 5w30 synthetic). I will do it at around 50% OLM or 4500 miles which ever comes first.
Yes, but there is no way it should go from 100% down to 75% in 100 miles of driving. Average outside temp around 65 degrees, mostly highway miles, probably cranked the engine 20 times in 7 days.
Purchase a new 2010 CTS with 51 miles. The Oil Life Monitor stated that oil life was 44%. The car was on the dealer's lot for 9 months, so length of time was a factor. The dealer said they would change the oil, so I took it in at 780 miles (3 weeks later) and the OLM was at 37 %. After the oil...