Tensile load distribution in a circular bolt pattern

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I am looking at an axle on a dump truck. The axle has two sets of dual wheel assemblies. The wheel assemblies are connected to the axle by a circular bolt pattern (see picture).
I have gone through and calculated the shear loading on from the weight of the truck and the torque distribution. However, I am having trouble getting the tensile load on the bolts. The way I see it, the load on the axle will cause the wheels to have negative camber which will result in the bottom of the bolt pattern having a high tensile load and decreasing towards the top of the bolt pattern. The way I started the calculation was using an equivalent load at the center of the bolt pattern causing a moment at the middle of the wheel where it meets the ground. I am not sure if this is correct and I was looking for any feedback or tips. My apologies if this is not explained well enough. If you need further clarification I will try. Thanks