Slight vibration 25-35 MPH
 

I have a 2006 Base (automatic) with 138K miles that has just started getting a slight vibration in the 25-35 MPH range. It only does it under load and i feel it in the seat back and in the steering wheel. It is only slight but just recently started. Running 265s that have roughly 80-90% tread remaining. Any suggestions?

Alignment?

Basics
If you feel it in the steering wheel front end, feel it in your seat usually the rear.
Check the drive shaft u joints and the rear pinion for slop.

I guess I should not be surprised if it needs U-joints considering it has almost 140K on it.