Energy Transfer Partners and Sunoco on Friday announced the successful completion of the previously-announced $5.3 billion merger, greatly expanding the reach of Energy Transfer's pipeline system.

Sunoco now becomes a subsidiary of Energy Transfer. The official news release, including specific financial terms, can be read here.

Sunoco has been trying to sell itself since late 2011 after posting losses for much of the past two years because of high oil prices and decreasing fuel demand.

Finding a buyer for the company and its aging refineries was considered a long-shot despite Sunoco's profitable logistics and retail businesses.

Energy Transfer gains 7,900 miles of crude oil and refined fuel pipelines from Sunoco Logistics Partners master limited partnership and give it a toe-hold in the Marcellus and Utica shale regions, increasingly productive sources of oil and natural gas.

Energy Transfer also acquires Sunoco's relatively successful chain of 4,900 gasoline stations that it could sell at a later date.

The deal was first announced on April 30.

Additional reporting by Dow Jones Newswires

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