The vibrations on mine are not steady. It may shake hard for a half mile and then be steady for 2 miles, then back to shaking. It does not mater if in V4 or V8 mode, tow mode, downhill decent disabled, traction control disabled, etc. I would think if it were a wheel, tire, driveshaft imbalance or torque converter issue then the vibration would be steady and not intermittent. It is like there is a harmonic issue. I have heard that the factory wheels are not very true. Wonder if you had two of those on the same axle if they would rotate to the same position and would vibrate until one wheel rotated out of synch with the other to cancel the vibrations? Do two wheel drives have this same issue? Anyone replace the full exhaust still have the issue? Anyone changed the shocks?