Mobil 1, the official motor oil of NASCAR and O'Reilly Auto Parts, the official auto parts store of NASCAR are joining forces to give racing fans a chance to win a trip to Las Vegas during the Sprint Cup Champions Week.

A total of four grand prize winners will win a trip for two to the 2010 NASCAR Sprint Cup Series Champions Week activities in December, a prize valued at approximately $3,750. NASCAR fans can enter by visiting www.mobil1.com/championsweek between July 1 and Sept. 30, 2010.

Each grand prize winner and a guest will receive:

-Airfare to/from Las Vegas

-A four-day, three-night stay at the Hard Rock Las Vegas Hotel

-VIP admission into NASCAR Victory Lap and NASCAR After the Lap presented by Tissot

-Tickets to the NASCAR Sprint Cup Series Awards Ceremony

To win a $10 O'Reilly Auto Parts gift card, fans can send an original register receipt dated between June 18 and Sept. 30, 2010, showing proof of purchase of either five one-quart bottles; one case; or one four-quart jug plus one one-quart bottle of any Mobil 1 oil product. Receipts can be mailed to Mobil 1 O'Reilly Gift Card Offer; P.O. Box 1091; Grand Rapids, Minnesota; 55745-1091.

In addition, fans can look for in-store promotional items at O'Reilly Auto Parts stores or on the O'Reilly Auto Parts homepage at www.oreillyauto.com.