Rear bearings are a wear item on these trucks. I replaced mine a few years back. I made a thread on here with some details awhile back. It made a significant difference in driving quality, although much of the noise and vibration was at higher speeds. We couldn't really drive above 70 without pretty significant shaking. The exception was on concrete highways. For some reason, I could do 80 there and the vibration wasn't an issue.I'm the proud owner of a 2005 Sequoia SR5 4x4 and couldn't be happier. I thought there was a problem with the tires or wheel bearings when I bought it but am coming to the conclusion that it's the front differential. From about 35 MPH to 60 MPH there is a very annoying cyclical vibration...www.tundrasolutions.com
Could it be the rear wheel bearings??