Importance of Trailer Wheel Pilot Hole Diameter

Updated 05/31/2016 | Published 05/28/2016

Question:

How much does the pilot hole diameter matter. Mine is about 2.5inch and I can find a rim with the same hole size. Im looking at either 1.8-12 4 on 4 as a spare

asked by: Bob L

Expert Reply:

The importance of matching a wheel's pilot hole diameter to the part of the hub that fits through it depends on the type of wheel. A hub-centric wheel uses the pilot hole to center the wheel on the hub and also to bear some of the total weight load (the rest going on the wheel bolts). Hub-centric wheels typically use wheel bolts rather than lug nuts to attach to the hub. If your wheels are hub-centric, you would want new wheels with the same pilot hole diameter as your current wheels because the wheels must center on the hub bore. If the pilot hole is larger, then the wheel will not stay centered on the hub and could move. If the pilot hole is smaller, the wheel may not fit on the hub at all.

On the other hand, a lug-centric wheel uses the studs on the hub and the lug nuts to center the wheel on the hub.

The trailer wheel/tire you referenced, Kenda 4.80-12 Bias Trailer Tire/Wheel # AM30660, is a lug-centric wheel with a 3.19-inch pilot hole. It is permissible to use this lug-centric wheel with a hub that has a smaller diameter bore, such as your 2.5-inch bore.

expert reply by: Adam R