NEW YORK (TheStreet) -- Add AutoZone (AZO) - Get Report, the second-largest U.S. auto parts retailer, to the list of those elated by lower gasoline prices.

Automobile owners are spending more on other parts of their car, maintenance and improvement, as the price of gasoline has fallen in recent months. Memphis-based AutoZone reported fiscal second-quarter earnings per share that surged more than 15% compared with the same period a year earlier. Shares were rising nearly 1% to $655.62, to extend its 2015 advance to about 7%.

Additional sales also bolstered AutoZone's share buyback program, as the company said it repurchased 43,000 shares of its common stock during just-ended fiscal second quarter, totaling $26 million. During its fiscal year, ended in August, AutoZone bought more than 600,000 shares of its common stock off the market, returning $326 million to shareholders at an average price of $530 per share.

And here's the thing, the company still has almost $550 million more shares to buy under its current authorization. This means investors that buy the stock now can still make money, despite the shares being at a 52-week high.  

What's more, even after roughly 10% stock gains in the past month, the shares are still cheap, trading at just 19 times trailing earnings. 

This means, aside from being discounted when compared with S&P 500 companies, the stock is also discounted to rivals Advance Auto Parts (AAP) - Get Report (P/E of 23) and O'Reilly Automotive (ORLY) - Get Report (P/E of 28) -- this despite AutoZone now having delivered 34 straight quarters of double-digit earnings growth. 

AZO PE Ratio (TTM) data by YCharts

Second-quarter profits climbed to $211.7 million, or $6.51 a share, topping last year's mark of $192.8 million, or $5.63 a share. This was enough to beat estimates of $6.38 per share. Revenue for the quarter ended Feb. 12 climbed roughly 8% year over year to $2.14 billion.

Equally impressive was the 3.6% year over year jump in domestic same-store sales, topping consensus estimates of 1.8%. This means, for stores that have been open at least one year, AutoZone's result doubled its growth expectations despite a 12% year-over-year increase in inventory.

The company said inventory grew due to higher product placement in its new stores, coupled with its recent acquisition of Interamerican Motor, which closed in September 2014.

All told, AutoZone, whose stock has risen almost 300% in the past five years, remains a strong value-creator in retail. Combined with its cheap stock and share-repurchase program, investors looking for consistent returns can do well in the next 12 to 18 months.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.