I've had an awful vibration at most any speed 30 and up. I can't pinpoint if it's more in the wheel or the floor or seats; it's just everywhere. It began when I mounted new tires and installed cal-tracs/pulled an overload the same weekend.
From a search I've seen the term "frame beaming" which seems like it applies to longer trucks than mine. One thing I have found today is I have up/down slack in my left front bearing. I'll get one on the way I guess.
I plan to make it to DiscountTire to get the tires "road force" balanced this week. I checked the U-joints best I knew how-put the truck in Neutral/set brake/shook driveshaft.
Anything else I need to check ?

I have seen this before with the hub assy being worn out and causing similar issues.

Replaced the hub today. I was a bit disappointed that I couldn't feel the slack once I had it off.
Vibration was reduced quite a bit but I haven't went but a few miles since the repair. Gonna get some interstate time tomorrow, maybe roll into Discount tire and get these things road force balanced.

to check u joints. drive for a while and get underneath. one starting to go will be hotter than the rest. i've had some burn out after i've checked for play and found none

I plan on going through the check per the DIY this week sometime. No slack stiing there and no squeak but I'm told now to put it in "n" /set brake and shake the joints.

OK. Checked the joints like I said (jacked rear up/brake off/shook driveshaft.) No slack in the joints and didnt see any difference in temp really. Changed the diff oil and t-case oil also. Diff oil was shot to hell, glad I changed it (only 50k on RP). Just as I suspected my leak between the trans & t-case is the case. Trans level hasn't changed but I only got approx 1 1/2 qts. out of the case from 2 orig. I guess (25k on that oil).

While shaking the tire with my foot I seen no slack and the only noise I heard was what I'm guessing is severe slack in the t-case chain/ rear splines. I need to find out what to lube those splines with and take care of that I guess.
That's what I have so far. Guess I'll try and get to Discount tire tomorrow and try the tires next.

JD, any updates?

Naw man, Sorry. Became tied up in some other things and never made it to discount tire. My last sled pull for a while is Sat so I may try again next fri.

Had the tires road matched at Discount tire 2 weeks ago. Vibration is gone or greatly reduced at all speeds except for 45-55. just as bad as it was in that range. On the plus side my surging braking is gone so it must have been a tire issue.
I'm about at my wits end with this. I have another set of PYO's, Guess I need to look into getting my other tires and see if swapping out the wheels/tires help.

It sounds like a tire issue….