U.S. stocks fluctuated as a gain in crude bolstered energy shares. Equities from Asia to Europe slipped on renewed worry a U.S. rate hike as soon as next week would damp growth, while billionaire investor David Tepper raised concern that corporate earnings expectations in America have gotten bloated. A two-day rally in Chinese shares faltered and a downgrade of Brazil's debt to junk underscored weakness in developing nations.

A rebound in global stocks this week ended in the U.S. on Wednesday after a jobs report bolstered the case for higher rates. Data Thursday added to that sentiment. The Bank of England said turmoil on the global financial markets hasn't shaken its economic outlook, fueling speculation the Fed may also look past recent turbulence at its policy meeting next week.

"We've stopped most of the panic about China collapsing and the world falling apart," said Ben Kumar, who helps oversee about $14 billion as a money manager at Seven Investment Management in London. "The next question we have to deal with is: is global growth strong enough to deal with a Fed rate rise?"