If he goes out shopping for replacement wheels, he'll need to know the bolt circle (5", 5-1/2", etc.) that the wheel studs are laid out on. That's the diameter of the circle upon which the lug studs are located.
He'll also need to know whether the wheels are lug-centric or hub-centric - that is, are they centered by the lug nuts or the center hub? If the wheels have tapered lug nuts, the wheel is lug-centric. If the wheels have flat-faced lug nuts with a washer, the wheels are hub-centric.
He will also need to know the hub diameter of the axle and the offset of the wheel. Today, trailer wheels are generally 0" offset.
2016 Ram Longhorn 3500 Dually 4x4 CCLB, 385/900 Cummins, Aisin AS69RC, 4.10
2014.5 DRV Mobile Suites 38RSSA #6972
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