What Could Cause This Wear Pattern?

A bad shock absorber causes the tire to "bounce" slightly and could cause the wear. You might not even feel it.

 

When the wheel is up on the jack and you set it to manufacturer’s spec, it's nice and easy to spin by hand and you think that's great. It's not. When you've got it loaded on the ground there's over 8000lbs on that wheel. A loose bearing allows that wheel to move in at the top and out at the front as you're going down the road. You really only have pressure on one part of each the inner and outer bearing. It's pretty hard for a tire to maintain an equal wear pattern when it's going down the road at an angle. Increasing the torque on a drive or trailer wheel bearing to 75 foot pounds distributes the pressure evenly around the bearing and keeps the wheel and tire running true. If your wheel is hopping you've got a problem that's causing it. Putting a new shock on might slow it down or even stop it but you're covering up the symptom, not correcting the cause.

 

I agree, @benjamin260_6.
It's trying to get warranty service on the non-wear parts that's hard.
Tech: "It's a wheel. It's round. It's got air. What more do you want, Burger King?"

 

I don't see a problem. Those tires have done well. Time to replace all of them before too long.

I did see a little spot here and there that might be something. But the overall vibe I got looking at them is they are getting tired after giving you good service. Winter is pending, anytime now will be a good time to replace all of them.

If everything else being true there should be no problems in alignment, inflation etc.

 

You need to buy a dial end play gauge tool that tightens up on hub an touches face of axle, when you go thru those steps you did after tork the outer nut it will tell how much end play is in the bearing,after a few trys it will show 001 to 005 free play or what ever the axle calls for it makes alot of difference in how long tires last with the setting right on the .oo2 setting

 

Put a tape measure across the rims... axle to axle. That looks like feather edging from misalignment. The measurement should be the same, side to side.

To get a rough idea how your alignment sits. Use a plumb-bob to mark the center of each axle on fairly level concrete, then measure between the marks.

 

I just went out and measured mine for ####s and grins. 28 1/2 on one side and 28 1/4 on the other. My tires wear nice and flat. Of course, that could be due to the fact that I don't run lugged tires either... Goodyear G399's all the way around.