One-Piece Vibration Probs.

[dsanchez]

I recently swapped in a one-piece drive shaft in place of the two-piece. This eliminated the problem with vibration during acceleration at low speeds. Now I have a nasty vibration above 40mph. It only happens when I'm coasting/when there's no torque on the driveshaft. I just got it balanced but that did nothing. I put new u-joints in it before I installed it.

The truck has a lift on it. Any suggestions?

 

[thegoat4]

Check your driveline angles. If you don't know how, find a shop who does and will let you watch.

If it's a suspension lift, I'd strongly suspect you got your pinion angle wrong.

 

[dsanchez]

I figured this was the case. It's got a 6" lift. The only weird thing is that the 2-piece had no problems at higher speeds. I'll take it into a shop to get looked at. For my information, is the pinion angle supposed to be the the same as the driveshaft angle ("in line" with it?)

 

[Sasquatch_Ryda]

No, it should be set at the same angle as the transfercase output. If you have a double cardan (cv style) is should be pointing at the transfercase output.

 

[dsanchez]

Hmmmm yeah that's strange then. I checked the angles on the flanges for both the transfer case and the pinion input. I used a clinometer. The transfer case points down at the ground at 6 degrees below horizontal. The driveshaft points down at the ground 5 degrees below horizontal. So they're to within a degree of eachother.

Or am I getting it confused? Should the axle be pointed UP as much as the transfer case is pointing down?

 

[Destroyer000]

Hmmmm yeah that's strange then. I checked the angles on the flanges for both the transfer case and the pinion input. I used a clinometer. The transfer case points down at the ground at 6 degrees below horizontal. The driveshaft points down at the ground 5 degrees below horizontal. So they're to within a degree of eachother.

Or am I getting it confused? Should the axle be pointed UP as much as the transfer case is pointing down?

i think you got it.. iam pretty sure the axle should be pointed up as much as the tcase is pointed down.