You may already have done this but please make sure your caster angle is correct. And along that line, please understand if you're running larger wheels/tires (from a diameter standpoint) on the rear than the front, your caster angle will be wrong...it will be too low because you've caused the rear to be higher than the front. A too-low caster angle will make your truck easy to steer but it will wander around like crazy and the faster you go the worse it will get...every time. So try to err on the high side if you can. If your steering box is adjusted correctly (many simply aren't), your drag link and tie rod ends are snug and your caster angle is correct (2 to 2.5 degrees positive is very good and 3 is excellent but will make driving around in parking lots harder---the shop manual calls for 1 3/4 +/- 1/2 degree), your truck should drive pretty nicely. Personal note: I've run mine at 1 3/4 degree and it will wander, but it stops doing that at about 2.25 degrees. More caster will cause your wheels to want to run straight and true and not wander but it will make it harder to turn because you're lifting the front end each time you turn the wheel. Please let us know if you don't understand that. Also, you'll hear people tell you your drag link ought to be parallel to the ground and this is true...but it doesn't happen in the AD unless you have pretty worn out springs. It slopes upward from the pitman arm to the steering control arm by an easily visible degree if your springs are new or not worn and sagging. Good luck!
