Someone help. Couple problems with 02 F250

[JPOWERStroke53]

Ive got a 2002 F250 7.3 liter with 6 inch lift and 35 inch tires. Ive got a slight vibration that kick in once i reach about 50mph and gets worse when I hit the brakes.
Also have a grinding sound/feeling when I reach about 65mph+ and let off the gas to just between engaging the throttle and letting is coast.
Can not figure out what is causing either of these problems and Im going crazy thinking about it.

[RedDye01]

The vibration sounds like a bad u joint. Had that happen before in a different truck. In my experience they are only good for about 125k with little towing. Throw a floor jack under each wheel and give it a shake. You may have a bearing going out up front. Common on these trucks. Expensive too as ford decided to make it a sealed unit instead of having replaceable bearings and races. Start there and let us know. If you find a bad u joint, remember to chalk a line down the entire shaft so you put it together exactly as it came apart

[JPOWERStroke53]

I have put new hub assemblies all the way around. Checked differentials. Replaced my u joints in the drive shaft and mid shaft bearing. Thinking of gettin a one piece shaft now. Replaced calipers and rotors (in case of just a warped rotor). Checked tie rods. I'm lost on what to do. It's only a rare thing it does every once in a while when it vibrates and when I apply the brake it gets real bad

[RedDye01]

Could be the track bar bushing. Have a friend with an e99 that had a similat issue. Sometimes a bump in the road would get it shaking a little.

[SuperCrutyPS]

Did you buy the truck with the lift and tires or did you put them on after you bought it?

Just throwing it out because I believe I've read something about shimming the carrier bearing? Maybe search for that to see what info comes up?

[StoneGuy]

Your bearings are in the steering knuckle. Any grinding noise would scare me. How is the power? Is the noise only at 65 or can you hear it on accelleration in lower gears?
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[JPOWERStroke53]

It's gotten worse to wear I hear it in the acceleration now. And when I let off the petal a little it gets louder. I can't figure out for the life of me what is goin on with it.

[JPOWERStroke53]

But my power is still great. I hit the has and she gets up and goes. Seems like it is shifting fine and everything.

[Jerry@tx]

do you have a spacer or adaptor for the wheels?

[JPOWERStroke53]

No I do not. Can that create the grinding I can feel?