A slowdown in off-road truck manufacturing rippled through Donaldson Co. as orders for its mufflers and other filters declined this spring and led it to miss investors’ financial expectations.

The Bloomington-based firm on Tuesday said its profit grew nearly 8% during the February-to-April quarter but that its backlog fell as orders plunged late in the period, its third fiscal quarter. Executives lowered their forecast for the rest of the fiscal year.

“Uneven demand and apparent destocking suggest that our customers are taking an increasingly cautious stance in light of market uncertainties,” Chief Executive Tod Carpenter said in announcing the performance.

Sales of cars and trucks in the U.S. have fallen every month except May so far this year. Donaldson executives said they also saw a drop-off in aftermarket parts and industrial filters.

Donaldson shares traded down through most of the day but rallied to finish at $48.72, up nearly 0.4%, on a day when broad market indexes also rose late and finished up more than 2%. Donaldson shares are now up 12.4% for the year.

The company said its profit amounted to $75.2 million, or 58 cents a share. Six analysts tracked by Thomson Reuters were expecting a profit of 63 cents a share.

Revenue rose 1.2% to $713 million. Analysts had forecast revenue of $745 million.

“Slowing in certain end-markets and destocking are not entirely surprising given recent commentary from other industrials,” said Matt Arnold, an analyst who covers Donaldson for Edward Jones.

Just this week, manufacturing surveys in the Midwest and around the country showed slowing activity and declining confidence, partly due to the impact of tariffs as the U.S. trade war with other countries deepens. Auto and truck makers this year through April had announced nearly 20,000 job reductions in the U.S., the most in a four-month period since the economic recession in 2008 and 2009.

Carpenter said Donaldson executives and employees would focus on things they can control like operational efficiencies, price increases and technology investments.

“We are balancing cost-optimization with further investments in strategically important businesses, like process filtration and our innovative air and fuel products,” Carpenter said.

In lowering its outlook for its fiscal year that ends in July, Donaldson said it now expects full-year per-share earnings to be between $2.20 and $2.24. The midpoint of that range is 12 cents lower than its previous guidance.

Despite lowering guidance, Donaldson executives still expect to report record earnings and sales for the full fiscal year.