NASCAR Xfinity Series at Auto Club Speedway
| NASCAR Xfinity Series | |
|---|---|
| Venue | California Speedway |
| Location | Fontana, California, United States |
| First race | 1997 |
| Last race | 2023 |
| Distance | 300 miles (480 km) |
| Laps | 150 Stages 1/2: 35 each Final stage: 80 |
| Previous names | Kenwood Home & Car Audio 300 (1997–1998) Auto Club 300 (1999–2002) 1-800-Pitshop.com 300 (2003) Stater Brothers 300 Presented by Gatorade (2004) Stater Brothers 300 (2005–2010) Royal Purple 300 (2011–2013) Treatmyclot.com 300 (2014) Drive4Clots.com 300 (2015) Treatmyclot.com 300 by Janssen (2016) Service King 300 (2017) Roseanne 300 (2018) Production Alliance Group 300 (2019-2020, 2022-2023) Former second race: Target House 300 (2004) Ameriquest 300 (2005–2006) Camping World 300 Presented by RVs.com (2007) Camping World RV Service 300 Presented by Coleman (2008) Copart 300 (2009) CampingWorld.com 300 (2010) |
| Most wins (driver) | Kyle Busch (6) |
| Most wins (team) | Joe Gibbs Racing (11) |
| Most wins (manufacturer) | Ford Toyota (11) |
| Circuit information | |
| Surface | Asphalt |
| Length | 2.0 mi (3.2 km) |
| Turns | 4 |
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Stock car races in the NASCAR Xfinity Series were held at Auto Club Speedway in Fontana, California from 1997 to 2023. The race was held as a 150 lap, 300 mile (480 km) race.
A second race at the track was also held during the fall as support to the Cup fall race from 2004 until the track lost its second Cup date after 2010.
No races have been held since 2023, as the track is currently undergoing demolition of the 2-mile oval.