NEW YORK, Oct 23 (Reuters) - Dow component Caterpillar Inc was among Thursday's biggest premarket movers, with the heavy machinery maker up on heavy volume following its results.
The stock rose 6.5 percent to $100.75 before the bell after posting revenue that beat analysts' forecasts. Caterpillar also said that its expectations for 2014 earnings continued to improve.
Also higher in premarket was General Motors Co, which gained 2.8 percent to $32.20 following its results. The automaker has been under heavy pressure this year, falling about 23 percent thus far in 2014.
On the downside, Yelp Inc slumped 11 percent to $62.32 on heavy volume a day after giving a revenue outlook that was below expectations. The outlook prompted many analysts to cut their price targets on the stock.
In the broader market, U.S. stock index futures were higher, adding to earlier gains on Caterpillar's results.
Futures snapshot at 7:43:
* S&P 500 e-minis were up 10.75 points, or 0.56 percent, with 219,271 contracts changing hands.
* Nasdaq 100 e-minis were gaining 22.5 points, or 0.57 percent, in volume of 34,148 contracts.
* Dow e-minis were up 108 points, or 0.66 percent, with 36,728 contracts changing hands. (Editing by Bernadette Baum; Editing by Lisa Von Ahn)