i was driving my truck the other day and out of no where it started the vibration that felt like i was riding the rubble strips and it never stopped and when i got home i pulled the front wheel off and the caliper and rotor and spun the hub and it made a slight vibration by just spinning it by hand i just replaced both front wheel hubs and u joints and i noticed gear oil coming out of the pass. side axle tube so the axle seal is bad but the front rear is still full and i checked the gear oil in the 5 speed the transfer case and the rear end and everything is full so my ? is what else in in the front end could cause a vibration like that and it starts around 20 mph in 2wd or 4wd and the faster u go the worse it gets

 

Tire out of balance? Caliper hanging up?

Do you feel it more thru the seat, or the steering wheel?

Does stepping on the brakes make any difference?

Do you have stock rims?

 

^ what he said plus bent rim or could be ball joints.

 

may be a stupid question / request but recheck that your 3 wheel bearing bolts didnt back themselves out at all since you changed them recently.

 

they r newer tires and stock rims was balanced last fall ball joints are good i feel in more in my seat and the floor board and yea it seems like if u hit the brakes it kinda stopped it but like i said i took the wheel and caliper and rotor off and spun the hub and u can hear something making noise in the axle tube could a bad seal on the outer axle shaft cause a vibration like let it move around or no?

 

Seals don't hold anything in place, just keep fluid from leaking out.

If you feel it more thru the seat, then it is probably the rear that is giving you the problem. Did this just kinda creep up, and progressively get worse? or, did you have something done, and then it started doing it? Are all the lug nuts tight?? Toss a wheel weight? (yeah, i have scraped a few of these off doing silly things off-road....)

Try rotating your tires, and see if the vibration changes.