Many thanks to all for all the VERY HELPFUL replies.
Checked the driveshaft phasing - everything is OK.
Revved the motor in neutral and didn't get any excessive vibes so I guess the flywheel bolts are OK.
A friend (he's the guys who spun balanced the new wide whites) suggested that the tires may be underinflated or have flat spots from sitting in the garage since last September. He suggested that if there are flat spots things may get better after a long drive. I upped the tire pressure from 20psi to just over 30 psi. As soon as the rain stops I'll go for a long ride and should know more...
The flat spots theory could be the answer. When I had to roll the truck forward to close the garage door, I noticed some resistance as if the tires were flat spotted. Once I overcame the resistance it rolled easily. The wheels didn't roll a full revolution so I can't confirm flat spots. As an afterthought It just felt like they were there.
Can anyone recommend a 6.70-15 tire pressure for freeway driving?
ThanKs Guys
