shaking over 60mph
what would cause a shaking over 60mph? new tires and alingment less than 800 miles ago, feels like the whole truck vibrates not just front steering wheel stays straght and no wobble if i let it go . and seems to smooth out a little at or over 70 mph. its a 04 tahoe z71
could be u-joints, front wheel bearing, CV shaft, Front diff issue. If it feels like the entire truck is shaking I would say possible ujoint
Google videos for "death wobble"
theres one of a green jeep........ if this is what you have, then your suspension is shot. virtually all of it.
you need all new bushings, inkage, and shocks....
how many miles are on the truck? does it have a lift?
Start with the basics, have your tires checked to see if they are out of round, Which I doubt is the trouble. The have all four tires rebalanced. That will probably cure your problem. If it doesn't then you are looking at a driveline issue.
yeah, alignment, well balanced AND well wearing tires. good CHARGED shocks and also dont forget that torsion bars sag after a while, so maybe turn your keys a little bit.
then we can look at steeing
(by CHARGED shocks, i mean; you hold it in your hand and it strongly expands and is difficult to push back down