WASHINGTON (Reuters) - U.S. industrial production rose in August, as strong output in auto manufacturing offset lackluster production in the rest of the factory sector.

An SUV moves through the assembly line at the General Motors Assembly Plant in Arlington, Texas June 9, 2015. GM-SUVS/ REUTERS/Mike Stone

The Federal Reserve said on Friday industrial production rose 0.4 percent last month after an upwardly revised 0.4 percent increase in July.

Economists polled by Reuters had forecast industrial production rising 0.3 percent last month after a previously reported 0.3 percent increase in July.

Manufacturing output rose 0.2 percent last month, powered by a 4.0 percent rise in motor vehicles and parts. U.S. producers assembled cars and trucks in August at an annual rate of 11.54 million units, the fastest pace since April.

But excluding motor vehicles and parts, U.S. manufacturing production was unchanged, the Fed said. Production fell for computers and electronic products as well as for electrical equipment and appliances.

The data could raise questions over how well U.S. factories are weathering an escalation of the U.S. trade war with China. The Trump administration raised tariffs on a range of Chinese imports in July, triggering retaliatory tariffs from Beijing on U.S. exports.

Other indicators have been more upbeat. A survey of factory managers showed activity expanded in August at its fastest pace in more than 14 years on strong demand at home and abroad, according to data released by the Institute for Supply Management earlier this month.

Manufacturing, which accounts for about 12 percent of the economy, has been supported by a strong domestic and global economy. But many economists see a risk that escalating trade tensions could undercut business investment.

Mining production rose 0.7 percent in August. Utilities output rose 1.2 percent.

With overall industrial production rising, capacity utilization, a measure of how fully firms are using their resources, rose last month to 78.1 percent from 77.9 percent.

Officials at the Fed tend to look at capacity use measures for signals of how much “slack” remains in the economy — how far growth has room to run before it becomes inflationary.