Unusal Inner LR Tire wear

[chevs10zr2]

I had my tires rotated in July, and had all normal wear on them. I went to go rotate them this last week (approximately 4,000 miles) and the driver side rear tire is wearing faster than the rest of the tire. Air pressure was fine.

I run 22 inch Nitto 305/45/22's it. Right side rear tire is fine.

I've searched and most unusal tire wear happens on the front. Any ideas as to what might be causing this?

 

[Kpwweb]

Could be three things:

1. They wore that way on the front and it is just now being noticed--I have done this before.

2. Tire issue--inside of tire has softer rubber and is wearing faster.

3. (Unlikely but possible) bent axle housing/bearing issue/rear axle issue causing excess camber or toe and wearing inside of tire on that side.

My vote is number 1. Has the alignment and thrust angle been checked lately?

 

[chevs10zr2]

When I had them rotated in July, there was no wear on that tire. The tire that's on the LF now (that was previously on the left rear in July, right before I had them rotated) has no inside wear.

#3 sounds possible, but I didnt think there was much to do on the rear with these in terms of alignment. I havent done an alignment (yet), only because I figured focus on aligments on the Tahoe's is generally up front. Maybe that's not correct though?

Could it be the rear control arms? If so, would would I be looking for ya think?

edit: changed from RF, to LF