What: Shares of heavy equipment parts supplier Meritor (MTOR) were down 9.8% at 11 a.m. ET on Wednesday after its quarterly results and outlook missed Wall Street expectations.

So what: Meritor shares have been walloped over the past six months due to its heavy exposure to the slowing global economy, and today's poor Q1 results -- adjusted EPS of $0.33 missed the consensus by $0.04 on a revenue decline of 8% -- coupled with downbeat full-year guidance only reinforce those macro headwinds. In fact, sales in the company's commercial truck and industrial segment fell $70 million to $633 million on currency weakness in Europe and Brazil, as well as economic softness in South America, giving analysts plenty of negative vibes over its near-term turnaround prospects.

Now what: For the full year, management now sees adjusted EPS of $1.65-$1.75 on revenue of $3.4 billion, down from its prior view of $1.70-$1.80 and $3.4 billion-$3.5 billion. "Despite the impact of lower production expectations in North America, we continue to execute well," said President and CEO Jay Craig. "Following another strong quarter, we remain committed -- and on track -- to achieving our M2016 metrics for margin enhancement, debt reduction and new business wins." Given Meritor's still-hefty debt load, sensitivity to macroeconomic weakness, and highly volatile shares, however, I wouldn't bet too heavily on that bullishness.