Feels Like It's Shaking Apart At 60+ Mph

[Tactical Bacon]

Pretty self explanatory. Only happens if I'm giving it some gas from 60 and up. Goes pretty much completely away if I let off the gas completely or floor it. Doesn't always happen. Started about three weeks ago, hadn't really done anything to it recently.

[shelbyluvv]

Could be a transmission mount. We need more info about the truck to make a better diagnosis.

 

lifted, engine, trans, all info about the truck

[yxmj]

Like the man says MORE INFO

 

My first to Guess-ta-mates are......Tire out of balance.....U-joint.........but really more info needed

[Tactical Bacon]

I really need to get after my sig. 91 Comanche Pioneer, 2wd, AX15, 4.0, shock height, has 31x10.5s on 15x8 Canyons from a Wrangler (been on it since end of October), both u-joints are relatively new as I replaced them myself less than 1000 miles ago, replaced the pinion yoke with one that uses u-bolts instead of u-straps around the same time.

[1987Comanche]

Georgia's vibration ('92, 4.0, AX-15, 2WD) started at about 50mph and, while there many contributors, the main culprits were loose U joint retaining straps and/or a bad trans mount.  Bad ball joints, control arm bushings, and track bar didn't help the problem any but weren't the main cause.

 

  Are you sure your U joint retaining bolts are tight?  I always Loctite mine in place...PO apparently didn't and they backed out.

[Tactical Bacon]

They should be (the yoke replacement was done by a local shopowner I know semi-personally, does quality work) but I'm going to get out after them with a box end wrench when I get home from work tonight. Though they could have loosened up in the weeks after having it replaced.

 

The steering wheel feels like its bouncing up and down, too, but that could be a trick.

[carnuck]

Pinion bearing going bad can cause issues like that too. It makes the driveshaft play crack the whip.