I can't figure my Axel's or tires out

[Kaidocl]

So here I am in Louisiana after my last trip 780 miles I notices one of my tires deflating so I stopped to add more air, as I check all the way around I noticed that one of my tires was coming separated at the wall and thread. So I look at my spare and it was a Goodyear marathon so I said no, I'm not adding this to our RW cause for the ones that know me this was the cause of the problem to begin with. So I called the Good Sam road side assistance and the got me a new 10ply tire for $410.
Here comes my question! So with my tires on, I used a straight edge and measured to the frame I was about 1/2 " off so I figured ok that's my problem spindle bend. But when the took the tire off I used same straight edge directly to the hub and I was under 1/8" witch is normal.
What would be the best or better suspension upgrade for me ? Anyone here having problems with 7k axel ? I don't think the 8k upgrade would make a difference. This tire wear also this is only happening on my front axel I posted a picture of my shackles few days back and the seem to never ride flat the front is always sitting pushed back.