Vibration @ 65

[Phoneman1985]

Need some suggestions. I had the transmission and transfer case gone thru and rebuilt. Got a new front driveshaft(it was missing when I got the truck). Not long after that I noted that when I run about 60-65 the truck starts to vibrate. The faster I go the worse it gets. So I dropped the driveshaft today to see if the trouble followed. It did. No driveshaft no vibration. I got the driveshaft from rock auto. I have a hard time believing that a brand-new driveshaft would be out of balance. Got to be something in the frontend but nothing I think of fits whats happening. Thoughts?

 

[Charlie]

 

[yevgenievich]

What transfer case?

 

[HotRodPC]

My 85 K1500 did the same thing. It was a well worn front axle. When it happened, it reminded me that I forgot to unlock my hubs. Assuming you have an NP208 in an 86 Model, in 2wd, the driveshaft should not be spinning. If you leave the hubs locked, then the wheels rolling will make the driveshaft rotate. I never worried about mine much because normally using 4wd, I'm not at highway speeds. I'd make sure the hubs are unlocked, and the Tcase is in 2wd.

 

[PrairieDrifter]

What kind of condition are your tires in?

 

[DavesJimmy]

Check wheel and tire balance, wear of tires, tie rods, draglinks, ball joints, u joints. All easy to do.