Trailer Wheel Bolt Patterns (4, 5, 6, 8 Lug)
Matching a replacement wheel to a trailer hub starts with the bolt circle, and the common configurations are not all alike. A 5 lug trailer wheel bolt pattern appears on many light and medium single-axle and tandem-axle trailers, while 4 lug, 6 lug, and 8 lug layouts serve different load ranges and hub sizes. The lug count alone is only the beginning. The spacing between the studs, the pilot hole diameter, and the load rating of the hub all determine whether a wheel actually fits and carries the trailer safely.
Essential answer
A trailer wheel bolt pattern is the arrangement of wheel studs on the hub, described by the number of lugs and the diameter of the circle they sit on. A 4 lug trailer wheel bolt pattern is typically found on light utility and boat trailers with smaller axle ratings. The 5 lug trailer wheel bolt pattern covers a broad middle range, from small cargo trailers to heavier single-axle and tandem-axle setups. A 6 lug trailer wheel bolt pattern generally indicates a step up in hub strength and load capacity, while an 8 lug trailer wheel bolt pattern is associated with heavier axles and higher gross vehicle weight ratings.
The pattern must be checked precisely because hubs with the same lug count can have different bolt circle diameters. Two five-lug hubs may look similar but will not interchange if the stud circle measurement differs. The hub's pilot diameter also locates the wheel, so a wheel can have the correct bolt circle and still fail to center on the hub. When selecting a wheel, compare the stud count, the bolt circle diameter, and the pilot hole as a set. This prevents a tight fit on the studs from masking a mismatched mounting surface that would allow movement under load.
