Having a vibration that doesn't belong

[ms8091]

Last week I decided to lock my hubs in my '99 f250 and test the 4x4. Everything went well and I disengaged them and put hubs to free. Shortly after, I start to notice what feels like a bad bushing or shock. It felt like every time I hit a bump, I would get a slight vibration. Fast forward to today, on the highway at 70 mph, the truck shakes violently, like driving on rumble strips at that speed. I stop, and there is nothing noticeable, just to see, I lock the hubs and drive on local roads only. Still has the same slight "bumping or vibration" but nothing crazy. I tried to unlock the hubs though and the drivers hub only goes half way and gets stuck. I had to use pliers to get back to locked. I am thinking maybe bad wheel bearings, but not sure. The hubs are newer Mile Marker premium hubs, so I doubt that could be it but not sure. Thanks in advance.

[ms8091]

[ms8091]

Anyone??

[Hank]

Wish I could help you? Just keep it bumped up. Maybe there will be more activity this weekend? Good luck!

[daveyburt]

front axle u-joint stuck?

[ms8091]

No, even with the axles locked everything is spinning. I am going to take it apart this weekend, hopefully it is very obvious. If anyone has any other suggestions, I would appreciate them.

[Tony V]

Yeah i'd check your U-joints. They freeze up. I also have a vib at 70ish, but i've changed both of my wheel bearings. Ive been looking for this rumbling for months now. I have changed my ujoints as well.

[daveyburt]

Originally Posted by ms8091

No, even with the axles locked everything is spinning. I am going to take it apart this weekend, hopefully it is very obvious. If anyone has any other suggestions, I would appreciate them.

You know you're truck best but, in case you may want to try....the way I found my issue was:

jack the whole front, unlock the steering (key on), and the hubs. push/pull on wheel to send the steering thru it's full range. reach inside and rotate the ujoint 1/4 turn, repeat sending steering thru full range. rinse and repeat until you've spun the ujoint all the way.

my steering actually LOCKED at a certain ujoint position...your's may not be that bad but, on it's way...

just figured I'd thro that out there...there's a lot in the steering/drivetrain that could cause vibes....good luck, it took me a few weeks to find my issue.

[Zaairman]

Check your wheel bearings (outter and inner). Grab your axle stub and give it a good shaking. If it has lots of play going into the bearing, you know which one to replace.

[ms8091]

Thanks Daveyburt, I will give it a try tomorrow. Yeah Zach, I still believe it may be the bearings but need to inspect thoroughly, I got to get it fixed this weekend, I hate driving my wifes car, its like being in a go cart.