Stifel Downgrades AutoZone, O'Reilly

In a report released Friday, Stifel analyst David Schick downgraded AutoZone AZO and O'Reilly Automotive ORLY from Buy to Hold.

No change in price target was given for either car part retailer; Stifel previously held a $570 price target for AutoZone and a $150 price for O'Reilly's

Analysts at Stifel believe AutoZone faced counter-cycle tailwinds in 2013 through the first half of 2014 and expect tailwinds to wind down over the next year.

Schick predicts weaker sales for O'Reilly for the company's upcoming quarter, despite its strong market effort in the near term. The note said recent retail sales for the sector slowed its heavy growth, currently up 3.3 percent year over year from February to April, and increased by 0.5 percent year over year in May to June.

AutoZone and O'Reilly have been battling in comp growth comparison with AutoZone growing flattish comps for its last four quarters and expectations of next year laps roughly by a three percent rate; O'Reilly increased from 2.5 percent in the last year to 5.7 percent over the next year.