dukedkt442

FWIW, many trucks today (especially crew cabs) have chassis vibrations due to the harmonics of frames that are too stiff, and the slightest road irregularities resonate through the truck like a taught guitar string. I personally dealt with this over the last 2 years on a '14 Ram and a '17 Silverado Z-71. The Chevy's issues are so well-known that they actually have an allowable range of vibration frequencies, and after testing my truck, the dealer said that its vibrations were within the acceptable realm from GM. On the Ram, both the service department manager and the general manager drove the truck and couldn't feel the vibrations, but a lead tech drove it and noticed it within minutes, and told me it was inherent to the design (due to chassis stiffness and cavitation from the large, open cab of a crew cab), and sure enough, the next 4 trucks (of varying years, including a brand new '17 at the time) exhibited the same. Some folks are more sensitive to vibrations than others; some drove my trucks and couldn't feel a thing, others got slapped in the face with it. The dealer replaced the input shaft bearing on the rear diff which helped some, and also did a "special" tire remount and balance, "sidewall massaging" they called itt, where the tire's drive surface was essentially pulled in with a rope, forcing the sidewalls against the lip of the rim, as according to them, air pressure alone sometimes isn't enough to fully, 100% seat the the bead, and that ever so slight wave in the bead manifests itself in high-spots on the tire that finely-tuned keisters such as mine can notice. A lot of the issues with the GM trucks for vibrations that don't go away have been traced to improper lash between the gears in the rear diff right from the factory, upon tear-down.

I've also cured many vibrations and shaking wheels by installing new rotors, not sure if you replaced all 4. A warped rotor hangs up on the pads, and that causes a vibration that can be felt. On the fronts on my E46, the shaking steering wheel would actually go away when applying the brakes, contrary to many situations where getting on the brakes worsened the condition.

4drocket

put some sand bags in the bed and see if that does it. I had this problem on my 99 f150 and was moving a pool table which stopped the shake so I put some slate in the bed and left it there. I know its an indian fix but it worked. also, my 06 f150 had a shimmy on the road and it was because I was running stock air pressure but it was too low once I bumped it up closer to max (about 50psi) it stopped. so did the cushy ride tho...

TheOldRaker

I wish you guys could see and feel the shake. I'll try and get some video of it, and put it up on youtube soon. I feel like I'm not describing how bad it is. I swear, I just can't see wind doing this. I wonder if I can just take the bed off and go for a ride.

TheOldRaker

Quick update. After everyone and their mother told me that I have a bent rim, or unbalanced tire, I finally bit the bullet, and put new rims on my truck this week. Guess what! No change at all. The truck still shakes like a mother!

The tech at the shop mentioned it could be my brakes, or my rack and pinion. Since I've already replaced the front rotors and pads, I'm going to be replacing the Rack and Pinion. Should have this done in a couple weeks, I'll check back then.

Oh, also, before I bought new rims, I removed the front drive shaft going from the transfer case to the front differential, to make sure the shaking wasn't coming from the drivetrain. While doing so, I noticed that those U Joints were totally kaput! So I'll be repairing those joints before putting that back in.