After minority shareholders voted in favour of a takeover last month, Suncor Energy Inc. ( TSX:SU )( NYSE:SU ) began integrating Canadian Oil Sands Ltd. (TSX:COS) into its operations. According to Suncor's vice president of strategy, the company "now has to find ways to reduce operating costs and share some operations with its other oil sands sites." Realizing potential synergies will be key to justify the buyout's $6.6 billion price tag, a price that was upped multiple times to appease prospective shareholders. Part of the deal includes assuming Canadian Oil Sands's debt load of $2.4 billion. Before the deal was completed, its credit rating was downgraded by three notches to junk at Moody's, making it the first large Canadian oil producer to receive a junk rating in at least a decade. Suncor's credit rating was also downgraded to Baa1 from A3. Stretched finances and sub-$40 oil will continue to put a strain on the combined company.