From April 2013 when I bought it, I've had a deep, seat-of-the-pants vibration (meaning it was likely coming from the rear) starting at 50 mph, peaking at 55 mph and ending at around 60 mph. Disconnected the rear drive shaft and that specific vibration was gone but it uncovered several more. Had the drive shaft balanced and reinstalled.

While the shaft was at the machine shop being balanced, the front left front ball joint assembly was replaced, (right was fairly new); new rotors on back and complete brake service performed including replacing the seized emergency brake assembly; tires rebalanced again (just done in Spring); front hubs disassembled, greased then reassembled; new vacuum lines to the front hubs; an alignment performed (front end only) and; new front anti-sway bar bushings installed (old ones were toast).

Even though it is a low mileage truck, it appears that nothing had been touched (meaning serviced) before ... maybe just brake pads replaced. Lots of seized parts when servicing all of the above.

Now I have two smaller vibrations. One at 35 mph (seems to be equally felt in steering wheel and seat of pants ... it's hard to tell and; another vibration at 70 mph ... this one is felt in the seat of pants. I'm running out of things to consider (and money and patience). Oh yes, a few weeks back I also replaced the transfer case and two differential fluids ... the rear diff was particularly "muddy" looking. I suspect it was never replaced before.

Any ideas? ~ Bugjr ~

 

Any ideas whatsoever?

 

When my truck was vibrating, I thought it was a bad tire.
Turned out the driveshaft threw a weight, but you already fixed that.