The 2009 Cadillac SRX 2WD V8 Base Model bolt pattern is 6-115 mm. This means there are 6 lugs and the diameter of the circle that the lugs make up measures 115 mm or 4.53 inches across. To get a close measurement of your 6 lug bolt pattern without a bolt pattern tool you should measure from the center of one lug to the center of the lug across from it.