I had my brakes (front and back) serviced within the past 5,000 miles, and just had the rear drums replaced 2 days ago (free of charge) when I experienced some squeaking. I then had two tires replaced- the other two tires are under 6,000 miles old- (balancing and allignment included) at a separate place right after getting the truck back for the brake work. While heading home with the two new tires, I experienced serious vibrations in the truck over 60 MPH. Tire folks say tires are properly balanced, but are checking it some more. I don't smell any burning or remember any chattering of the brake pedal. Is the problem tire-related, or brake-related? I would like to know which shop to approach. Thanks!