Lithia Motors continued on its course of record earnings in the second quarter.

Lithia Motors continued on its course of record earnings in the second quarter.

The Medford-based auto retailer reported Wednesday the highest quarterly adjusted net income in its history: $35.2 million, or $1.34 per share, up 29.1 percent from the second quarter of 2013.

Including the profit from sold or shuttered units, Lithia's net income for the quarter was more than $38.3 million, up nearly 50 percent from the $25.6 million reported in the second quarter of 2013.

The bottom-line success was fueled by 21 percent revenue growth to more than $1.2 billion, up $213 million from a year ago.

"For the first time in our history, same-store sales experienced double-digit increases in all four business lines," Bryan DeBoer, Lithia president and CEO, told analysts and investors during a morning conference call.

Service, body and parts sales grew 10 percent, thanks to a 15 percent burst in warranty activity and customer-paid maintenance rising by 10 percent. Lithia also benefited from the acceleration of auto industrywide sales, with a rate in June that would equal annual sales of 16.9 million vehicles, the highest level since July 2006.

During the first half of 2014, Lithia showed 25 percent growth in its earnings to $2.36 per share.

The quarter was filled with transactions, including the largest in company history during June. However, the $362.5 million acquisition of DCH Auto Group won't make its full impact on the balance sheet until after it closes in the fourth quarter.

"The acquisition market remains robust," DeBoer said.

Lithia finished June with $28 million in cash and $84 million in available credit, as well as $216 million of unfinanced real estate, giving the company potential liquidity of $274 million.

During the call, Chief Financial Officer Chris Holzshu said that Lithia plans to expand its borrowing power to $1.6 billion. That, he said, ''would give us plenty of dry powder to continue to execute on acquisitions as they come up."

"Our goal is to maximize our borrowings obviously at the lowest possible cost," Holzshu said. "Right now, we feel comfortable that for the acquisitions that we're doing, expanding our facility, continuing to take on, earn or use the free cash flow that we're generating, in excess of $100 million a year, is what's prudent. But if and when a larger acquisition comes to market, we'd understand that we have currency, with the stock that we have, and we will use it when the time is right."

The auto retailer announced a 16 cents per share dividend payable Aug. 22 to shareholders of record on Aug. 8.

Lithia shares reached $97 Wednesday before settling for a 4.6 percent gain at $94.59 at the close of trading on the New York Stock Exchange. During the quarter, Lithia repurchased 30,000 shares at a weighted average price of $75.36 per share.

Reach reporter Greg Stiles at 541-776-4463 or Follow him on Twitter @GregMTBusiness, friend him on Facebook and read his blog at Edge.