Bad Vibration On Freeway 2Wd Ba-10

[chastings]

I had a trip Wednesday morning, drove the faithful manche to the airport and by the time I got there my truck developed a pretty nasty vibration. I noticed it after passing a semi. I could hear a slight roar and feel a vibration through the shifter, the clutch pedal, the brake pedal and somewhat in my seat. The noise sounds like it was originating in the back, but I've been wrong before. At slow speeds everything is normal; transmission sounds the same, no strange noises, but once above 60 there is a very noticeable vibration. It doesn't matter if you're neutral (coasting on the freeway), in gear, or in gear with the clutch engaged, the vibration won't go away until the speed is signigicantly decreased. It doesn't feel like a tire/balance issue, it doesn't quite fit the bill for bad carrier bearings either. I'm leaning towards u-joint or maybe even a loose wheel? I was late for my flight so I couldn't even investigate... but I return tonight and may have to either limp it home (after checking lug-nuts) or have the wife pick me up after I remove the d-shaft. The slight roar has me scratching my head, if I weren't 1500 miles away I'd have it diagnosed and fixed by now....

Thoughts?

[Eagle]

U-joint.

[chastings]

Thanks, good to hear!

[armyofchuckness]

Was that the solution? My MJ just started doing the same thing! I have a 2WD I4 with a 4speed. It starts around 35 and doesn't go away until I get back below that speed. It doesn't matter if I'm in gear or not. Turning the wheel does nothing. The vibration doesn't change pitch with speed. I just bought four brand new tires thinking that it was a balancing issue caused by improperly sized tires. (They were old and needed replacing anyway.) I was dismayed to see that it didn't solve the problem. I had to immediately leave to drive three hours to the inl-aws and had to leave the Jeep behind, so I'm stewing trying to figure out what the problem is.