My 98 chevy silverado 5.7L constantly shakes while driving. Changed out shocks

[Sid]

but still instable? Problem? I have changed out the shocks, had front end alignment, and had wheel rotate and balance but the problem still exists. Wondering whats the problem?

[Robert e. L]

check the inner and outer tie rods or the idler arm

[Erik D]

it sounds like the problem is in the tie rods or the rotors could be very out of round as well.

[oodlesoanimals]

Yep, it could be all the things that these guys up there have mentioned...and it could also be a bent or loose drive line.
Try checking out all of the easy things first....things that you can do yourself.....cheaply. And go from there.
Good luck