89 vibration

[bart6180]

when i take the truck on the freeway it start vibrating at 60mph, and smoothes out about 75mph, i just got the truck, and it looks like it could use new tires, could they be causing the vibration

 

[bluesman17]

Check the u joint first, get under it with it in park and see if you can twist the driveshaft at all.

 

[bart6180]

drive shaft is tight, no movement at all

 

[orion]

I just went through this with my 86, had picked up some new(to me) rims, the 92-96 aluminum style 10 hole no rivet, had Discount tire mount my tires, and balance rotate...voila, I was at 75 on the freeway without knowing it, the "rumble zone" was gone.

I checked ujoints, driveshaft bolts, u bolts on leaf springs, and motor mounts as I had read that all of those could cause vibration.

Lucky for me the balance did it, my tires were new too, and the vibration was very noticeable. Amazing what those little weights, or lack there of will do.