Truck engine maker Cummins (CMI) announced Tuesday that it is cutting its full-year revenue forecast in light of slowing economic growth and weaker-than-expected demand. Although the company initially forecasted full-year top-line expansion of 10%, it now expects revenue to be flat year-over-year. The firm specifically cited softening order trends for trucks and power generation equipment in the US. Further, demand hasn’t quite grown as quickly as Cummins had thought it would in key, growing markets like China, Brazil and India. Some of the negative impact will also come from the US dollar strengthening against other currencies.

Cummins now expects second-quarter revenue for 2012 to come in at $4.45 billion, which is about $500 million short of the $5 billion analysts were expecting. That figure is also down about 4% compared to the same period a year ago. On a more positive note, the firm expects strong cash flow generation as it raised its quarterly dividend from $0.40 to $0.50 per share. The firm’s balance sheet also remains pristine.

Cummins is certainly not the first company to cut its outlook this quarter, and we think it underscores the emergence of divergent economic trends. Along with reduced outlooks from Applied Materials (AMAT), Informatica (INFA) and Seagate (STX), it looks like business spending will continue to face pressure in the back half of the year. Notably, none of the trends seem to be very consistent, but rather seem unique to each firm. The strong dollar is hurting results for US-based multi-nationals, while several other struggling firms are heavily dependent on slowing business investment.

Still, plenty of other companies point to positive results in the US economy. Alcoa, for one, continues to be extremely bullish on demand in the aerospace segment as Boeing (BA) works to fulfill its tremendous order backlog. Further, car dealer AutoNation (AN) and almost every auto maker announced strong sales in the US in June. Footwear giant Nike (NKE) reported strong North American results in its fourth quarter late last month, though its aggregate results were dragged down by China and Europe. Even same-store sales for June at most retailers weren’t awful. Meanwhile, homebuilders like KB Homes (KBH) and Lennar (LEN) have reported stronger-than-expected results and growing backlogs.

While we’re not ready to throw in the towel on the US economy, we think problems persisting from slowing global growth will provide a stiff headwind for corporate earnings in the near term. However, we think this has created several interesting opportunities, especially in areas where there are pockets of demand strength (namely aerospace and domestic autos). For example, one of the largest holdings in the portfolio of our Best Ideas Newsletter, aerospace-component supplier EDAC Tech (EDAC), finished up nearly 12% today, despite the S&P 500 falling nearly 1%. The firm registers a 9 on our Valuentum Buying Index, and it is heavily exposed to ongoing stength in commercial aircraft deliveries.