Noisy 4x4 and Vibrations

[ShadowFox]

I have a 2001 F250 Ext Cab with 7.3/Auto with ESOF. 170k.

I bought the truck almost a year ago and this is the first pickup I have owned. I never used the 4x4 until this winter, but when I did, it was noisy (Lots of "Thud Thud Thud" sounds and the whole truck vibrates). It was kind of annoying but not anything that the stock radio wouldnt mask. Then as the winter kept passing, the noise and vibration got louder. Then when I was doing an oil change a few weeks ago I found a vacuum line undone by the driver's side front wheel. I cut the end as it was damaged, plugged the hose back in and used a hose clamp on it. That didnt change anything.

Then the other day was rather bad weather wise, so I kicked the 4x4 on and it was even louder. Then all of a sudden...BOOM! The transfer case exploded. I got the truck towed back to my house, and ordered a used tcase from LKQ. Put the new case in, filled it with mercon v atf, and took it on a test drive. Had the hubs in lock with the ESOF on 4H and it made the same noise as before. Put the hubs on Auto and ESOF in 4H and same thing. Turned the ESOF to 2H and noise/vibration goes away. Im scared to drive it in 4x4 now.

What is wrong?????

[ipz2222]

Differant size tires. running 4wd on asphalt is a no no.

[bob harris]

He is right, dont use 4WD on tar roads, will bind up front and rear wheels

[ShadowFox]

I understand Im not suppose to go out on dry pavement and decide to randomly use 4x4. But when the transfer case broke, we got 6" of snow that day and the roads were iffy. So am I not suppose to use 4x4 on roads at all then?

[jc82chevyman]

No there is something wrong it sounds like a hub or u joint is binding up in the winter mine lives in 4x4

[cghoerichs]

Yeah, something was wrong. You can run on the road in 4x4. Not good around corners on pavement in 4x4, but just running on pavement doesn't cause the tcase to explode. Loud noises and grinding said that there was a problem not addressed.