Gasoline prices are low and people are hanging on to their cars longer. That's a great combination to fuel sustained upward movement in shares of auto parts retailer AutoZone (AZO) , which reports fiscal second-quarter earnings early Tuesday.

The stock, at $780, is up 5% year to date and 21% over the past year, outperforming both the S&P 500 (SPX) index and SPDR S&P Retail ETF (XRT - Get Report) during both spans. AutoZone, the market share leader in the auto parts market, has been rewarded for its streak of double-digit profit gains and consistent revenue growth.

Now is an ideal time to own shares.

For the quarter that ended in February, analysts, on average, expect the company to earn $7.28 a share on revenue of $2.26 billion, marking year-over-year growth of 11.8% and 5.5%, respectively. For the full year, ending in August, earnings are projected to climb 13% year over year to $40.68, while revenue of $10.75 billion would mark a 5.5% year-over-year rise.

Headquartered in, Memphis, Tenn., AutoZone has made profitability and returning value to shareholders a priority. The fact its profits are projected to grow at more than twice the rate of revenue serves as some evidence. Those profits have only just begun to climb, if a recent report from U.S. Department of Transportation is right.

Consumers not only are driving their cars more, they're also putting more miles on the cars per trip, hitting more than 264 billion miles last November (seasonally adjusted), noted the report. Even more of a benefit to AutoZone is the fact the average age of vehicles on the road reached 11.4 years, said the Department of Transportation. So consumers are keeping their cars longer.

This combination is a boost to AutoZone because older vehicles will typically require more service, part replacements and accessories. Combined with the average cost for oil falling below $30 per barrel recently, it would seem to be time for a road trip. In that vein, buy AZO and enjoy the ride.

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