(Adds details, shares)
July 28 (Reuters) - Goodyear Tire & Rubber Co, the largest U.S. tire maker, reported lower-than-expected quarterly sales as demand for tires weakened, and slashed its full-year forecast for segment operating income.
Shares of the company were down 8.7 percent at $32.41 in premarket trading.
"Our second quarter results reflect the impact of volatile raw material costs and an increasingly challenging competitive environment, particularly in the United States and Europe," Chief Executive Richard Kramer said.
Demand weakened in both the original equipment and replacement market, Kramer added.
The Akron, Ohio-based company's sales in the Americas slipped 2.9 percent to $2.03 billion, while sales in Europe, the Middle East and Africa (EMEA) fell 11.7 percent to $1.11 billion.
The company lowered its forecast for 2017 segment operating income to a range of $1.6 billion to $1.65 billion, from its previous forecast of $2 billion.
Asia Pacific was the lone bright spot, with sales climbing 2.8 percent to $543 million.
Net income fell to $147 million, or 58 cents per share, in the second quarter ended June 30, from $202 million, or 75 cents per share, a year earlier.
On an adjusted basis, the company earned 70 cents per share, in line with analysts' average estimate, according to Thomson Reuters I/B/E/S.
Revenue fell about 5 percent to $3.69 billion, missing estimate of $3.70 billion, according to Thomson Reuters I/B/E/S.
Up to Thursday's close, shares of the company had risen 15.3 percent this year. (Reporting by Arunima Banerjee in Bengaluru; Editing by Amrutha Gayathri)