We've updated our reliability stats for the XC90 to include owner experiences through September 30, 2016. In terms of repair trips per 100 cars per year (lower is better):

2016 XC90: 64, high
2010 XC90: 38, low, very small sample size
2008 XC90: 55, moderate, small sample size
2007 XC90: 71, moderate
2006 XC90: 79, moderate
2005 XC90: 58, low, very small sample size
2004 XC90: 37, low, small sample size

Additional participants always helpful, especially for years without stats or with small sample sizes.

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Volvo XC90 reliability ratings and comparisons