Truck is a 2003 GMC Sierra 4x4. It started about a month ago when I took my truck to Firestone for an alignment. They aligned it and it stayed aligned for a couple days till I noticed the steering wheel started to be off center when tracking straight. It slowly got worse and worse until the steering wheel got to the point where it was 30* right of center when tracking straight. Going over bumps or any kind of undulation in the road caused the truck to pull hard to either side. I got under the truck and noticed this in the picture.
That is the driver side, passenger side nut is tightened securely against that sleeve.
I took it back to them under warranty, and they realigned it. Again, it stayed aligned for a couple days, then eventually same symptoms as before.
Is there anything that has wore out in the front suspension causing this reoccurring problem? I wanted to get some advice before I take it back again or start throwing money for parts. Thanks!