In March 2013 i test fit 17" CTS wheels in an effort to get additional sidewall and an acceptable highway ride. The nuts & bolt pattern fit, but the rim was too small a diameter to clear balancing weights. The 17" rim was very very close to the caliper. An 18" would have likely fit, but never tried it.
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2010+ CTS (not CTS V which is 6 lug), XTS
5 x 120mm “High Positive Offset”
XTS Rim is Alloy, 19 x 8.5 / “JXIS39”
Buick Lacrosse, Lucerne, Park Ave, 1986-2009 Regal, Riviera; 2002-2009 DTS, CTS
5 x 115mm “High Positive Offset”
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2010+ CTS (not CTS V which is 6 lug), XTS
5 x 120mm “High Positive Offset”
XTS Rim is Alloy, 19 x 8.5 / “JXIS39”
Buick Lacrosse, Lucerne, Park Ave, 1986-2009 Regal, Riviera; 2002-2009 DTS, CTS
5 x 115mm “High Positive Offset”
