Vibration Issue @ speed over 55 MPH

[SalTahoe12]

Hello Fellow Tahoe Owners,
I need some help. I have a 2012 Tahoe. I have a vibration at speeds over 55 mph. The truck has been doing this for the past two years and I cant find the problem, nor can my mechanic. It feels like a tire balance issue, but I have been through 3 sets of tires and still vibration is there. Well here it goes....I have also put:
new shocks and struts,
new front axles,
new u-joints,
new calipers and rotors,
Transmission and Motor mounts checked, all good,
Drive shaft checked, all good,
Tires road force balanced.
After all this still have the vibration. I have read that other people have complained about this vibration on 2012 models and up, and even on the 2015/2016 models and GM tells them the vibration is in Spec/Tolerances because they cant even fix this problem. Has anyone had this issue or have heard of it, and if so has anyone been able to fix this problem.

Thanks

 

[spectralen]

I have a 2013 PPV and have a slight vibration at just over 70. My truck is bouncing all over at low speeds because of the police springs.
Did you check your driveshaft?

 

[SalTahoe12]

hey spec,
yea mechanic said drive shaft is good. kinda given up on it, I think it is what it is...thanks for the reply thou

 

[spectralen]

I understand totally

 

[shane.nelson]

So I'm having a vibration issue as well on my 99 Tahoe 4x4. I've done a lot, and I mean a lot to try and solve the problem. This is just a list of what I've done.
-Rebuilt Front and Rear diff.
-Rebuilt transfer case
-Rear drive shaft re-balanced with new slip yoke and u-joints
-New front axel half shafts
-New front wheel hub assemblies
-New 265-70-18 AT Tires on GM wheels off of a 2010 Tahoe
-New upper and lower ball joints
-New(ish) shocks all the way around
Any idea what else it could be? I didn't mind spending the money on these things, even if it didn't fix the problem. I plan on keeping the Tahoe for a long time. However this vibration at 65+ mph is getting annoying. The steering could be tighter to be honest. I kinda thought motor mounts as well. They are original with 160k on the clock. Idler and pitman arm are original as well.