Special items of $9.1 billion contributed to General MotorsÔÇÖ $15.5 billion second quarter loss, the third biggest quarterly loss in its history, as US sales continued to plunge. ┬á GM took a $3.3 billion charge for buying out the contracts of 19,000 hourly workers who left at the end of June, and $2.8 billion for its exposure to bankrupt former parts unit Delphi Corp. It also wrote off $1.3 billion because the falling price of used vehicles cut the value of leased automobiles owned by its financing unit, GMAC.