Vibration at 30mph+

[Daly]

Not sure if this is where this question should go, but like it says, I have a vibration that starts at 30mph and starts to go away after 60mph, but never really goes away. The tires have been road force balanced and they check out. I'm thinking it could be a universal or a transmission mount, maybe even the torque converter. But is there anything else I could be missing? I'm going to start with the cheapest fix and go from there, but has anyone else had this experience and fixed it?

 

[deadbeat]

Driveshaft, frame beaming, drum out of balance.

 

[K1500_Mike]

I'm encountering the same problem, and what I was told was that my G80 Limited Slip was toast and the clutch plates were vibrating in the diff causing the noise. Apparently a cosmetic noise, minus the fact that I don't have the Limited Slip anymore. I'm ok with it cause my 14 bolt Semi Float is just gonna get a Detroit at some point and I can live with a little noise as long as hell itself isn't being spawned beneath me.

 

[jedifan]

Check the universal joints.