I recently (3 months ago) bought a 2010 dc Trd or (4.0l v6) manual. It came with duratracs (265/75/16) and a leveling kit (bilstein 5100s, aal). The tires supposedly have about 30000 miles on them. I bought the truck when it had about 25000 on the tires and last week rotated the tires front to back, not diagonally. I can't say whether the previous owner ever rotated them.
Now I'm finding that at 60-70 mph, the steering wheel vibrates strongly side to side, about half an inch in either direction. That is rotating half an inch, back and forth, relatively quickly. It does it somewhat intermittently, and I can't seem to find any variable that makes it do it other than speed. At 75, it doesn't happen (or it does so little it doesn't matter). The alignment seems fine, even when it does the vibrating. No bouncing, so I don't think the wheels are out of balance.
Could they just be worn really oddly because they weren't rotated? Is this something that will work itself out, or do I need to tires? They definitely show some wear, but I'd expect them to get at least another 5-10k miles. They have always been fairly loud, but are my first ATs so that might be normal. They don't seem to be much louder now than before I rotated them. I have about 7 hours of highway use on them since I rotated, and there seems to be not much change, but maybe it happens a little less frequently. I'm a bit worried because I'm driving Virginia-Colorado next week and really don't want to have any issues.
Any thoughts as to what might be causing this? Is this a duratrac problem? Should I just put them back like they were? New tires? Also, what pressure are people running these at? Could low/high pressure be causing this?