Bolt Patterns
A bolt pattern is the stud count plus the diameter of the circle those studs sit on. It is the one measurement that has no workaround: the pattern either matches or the wheel does not bolt on.
How to read it
In 8x170, the 8 is the number of studs and 170 is the bolt-circle diameter in millimeters. Patterns are also written in inches — 6x139.7 is the same as 6x5.5". Some wheels are dual-drilled and accept two patterns.
Common truck patterns
Ford F-150 (2004+), Expedition, Raptor
Shop 6x135 wheels →Chevy/GMC 1500 (older), Silverado, Tacoma, Tundra (older), Titan, Ram 1500 (older)
Shop 6x139.7 (6x5.5") wheels →Ford Super Duty F-250/F-350 (1999+)
Shop 8x170 wheels →Chevy/GMC 2500HD & 3500HD (2011+)
Shop 8x180 wheels →Ford F-350 dually (2005+ DRW rear applications)
Shop 8x200 wheels →Chevy/GMC 3500HD dually (2011+)
Shop 8x210 wheels →Ford F-450/F-550 dually
Shop 10x225 wheels →Dually patterns are different
One-ton dually trucks often use a larger rear pattern than half-ton trucks, and dually kits combine front, rear outer, and (on some designs) rear inner wheels. Always order the matched kit rather than mixing positions.