Stock index futures pointed to a flat open on Friday as data showed the economic expansion gathered speed in the fourth quarter, though a touch below forecasts.

The economy grew at a solid 3.2 percent rate in the fourth quarter as consumer spending accelerated, according to the advance reading on gross domestic product. Analysts forecast growth of 3.5 percent.

This is a respectable number, but it suggests that the strongest growth estimates for the year may be too aggressive, said Bruce McCain, chief investment strategist at Key Private Bank in Cleveland, Ohio. This could take a toll on a market that's gotten pretty overextended.

The Dow and the S&P have struggled to move past major technical levels -- 12,000 for the Dow and 1,300 for the S&P -- with technical measures indicating the market could be overstretched.

Still, the S&P ended at a new 29-month high on Thursday, and the Dow was on track to notch its ninth straight week of gains for the first time since March-May, 1995.

S&P 500 futures rose 0.7 point and above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures dropped 4 points, and Nasdaq 100 futures rose 3.75 points.

Dow component Chevron Corp's quarterly profit was up from the prior year on a sharp rise in oil prices, but the stock fell nearly 1 percent to $94 before the bell.

Ford Motor Co shed 5.6 percent to $17.74 in premarket trading after it reported a steep drop in its quarterly profit due to a charge for debt payments. Rival automaker General Motors Co lost 2.5 percent to $37.70.

Ford results were pretty ugly, said James Dailey portfolio manager of TEAM Asset Strategy Fund in Harrisburg, Pennsylvania. With the stock adopted by momentum players, Ford has risen almost 12 percent from the start of January to the Thursday close.

When that happens you need to have the company beat in the quarter and raise its outlook in order to keep moving higher. When that doesn't happen, the stock gets pummeled, Dailey said.

Late Thursday, Dow component Microsoft Corp posted a dip in profit, and online retailer Inc recorded revenue below the consensus view.

Microsoft rose 0.2 percent to $28.93 before the bell, while Amazon sank 7.2 percent to $171.16.

(Editing by Jeffrey Benkoe)