was able to lower truck down another 0.5" few weeks ago, but now at speeds between 20-30mph, and 60-70ish mph, i get a front end shake, shimmy, etc. (steering wheel moving left / right very quickly)

Just pulled a wheel now, and got two long braker bars out to go over everything once again.

Top two (21mm?) bolts on control arm took a few small moves to get it "real phuckin tight."

anything else i may have overlooked?

list some causes (hope a wheel isnt out of balance! )

 

1) Truck too low
2) Truck wheels too big
3) Too many video screens in truck

Thats a start for you

 

Ummmm yer basic shakes:

Alignment
Brakes and rotor hot spots
Tire wear (uneven)
Tire Balancing
Bearings
Upper Control Arm bushings

Take the simplest cheapest and work your way up the list ....

They're all good things to check

 

the 70mph shaking has been shown to be an exhaust system vibration.

 

Say What???

 

Thanks.. tightning the upper and lower control arms "seemed" to make a big difference(guess they were not as tight as i thought), but it can still be noticed.

 

check the weights on the wheels, im sure there stickons
so you might have knocked one off .

 

Have you checked the angle of the drive shaft? I've heard of some vehicles being lowered to much that the driveline is at such an angle to cause a vibration. This can usually be corrected by shims if that's the problem. Good luck.

 

Jack up the front end and give the wheel a good spin and stare at outside diameter to watch for high spots which could indicate tire seperation.

That would be all the time though.

Tire pressure the same?

In a few weeks wear you could have gotten some odd tire wear.

How about swapping with the back tires and see if it acts the same...

 

Mine shimmey's real bad every time I drive up this road.

http://www.mccullagh.org/image/d30-3...ad-tracks.html

 

Hah, the first thing that popped in my head with this posts title was the scene from AIRPLANE.

"She's begining to shimmy" and "She's begining to shake" with the big bewbs flying around.

lol.