Rotating the Driveshaft?

[Domin0]

Howdy,

Long story short: Local shop didn’t draw an index mark on the attachment point, and seem to have bolted the driveshaft back on in a different orientation, causing a driveline vibration.

I have no experience working on driveshafts, so I’d like to attempt to tackle this myself and learn something. I’m just unclear on what the process for rotating the driveshaft is? Remove the rear bolts, put it in neutral, twist 90° or 180°, and rebolt? Or does the entire assembly need to be removed and reinserted?

Apologies if this comes off as asinine.

 

[New recaros]

I bet the drive line is not the problem. They are balanced.

 

[Domin0]

I bet the drive line is not the problem. They are balanced.

Wheels & tires were perfectly balanced, and there weren't any signs of u-joint issues prior to going in. Can't think of any other potential cause.

 

[nikhsub1]

Why did they drop the driveshaft?

 

[shigman]

Was it only a driveshaft or also a differential or transfer case thing?

 

[rschap1]

As mentioned driveshaft should be balanced and orientation (clocking) should not have to be anything specific.
I would look for play in the yoke and/or u-joints if pretty sure driveshaft is the culprit.
Transfer case output and pinion bearing next.

 

[FordTechOne]

Howdy,

Long story short: Local shop didn’t draw an index mark on the attachment point, and seem to have bolted the driveshaft back on in a different orientation, causing a driveline vibration.

I have no experience working on driveshafts, so I’d like to attempt to tackle this myself and learn something. I’m just unclear on what the process for rotating the driveshaft is? Remove the rear bolts, put it in neutral, twist 90° or 180°, and rebolt? Or does the entire assembly need to be removed and reinserted?

Apologies if this comes off as asinine.

You’ll want to remove it at the pinion flange, and rotate it 90 degrees. The bolts are considered one-time-use, but once you get it balanced you can add medium thread locker to the bolts. Torque spec is 76 on-ft.

The Workshop Manual specifically calls out index marking the driveshaft, because although it’s technically balanced, you can end up with a type of tolerance stack of that can result in a vibration.

 

[Domin0]

You’ll want to remove it at the pinion flange, and rotate it 90 degrees. The bolts are considered one-time-use, but once you get it balanced you can add medium thread locker to the bolts. Torque spec is 76 on-ft.

The Workshop Manual specifically calls out index marking the driveshaft, because although it’s technically balanced, you can end up with a type of tolerance stack of that can result in a vibration.

Thank you!

 

[nikhsub1]

When I replaced my failed pinion seal I made sure to mark the driveshaft bolt and where the flange comes out of the diff to make sure it went back exactly as it came in.

 

[New recaros]

I think you’re getting half of the story. Take a look at this article. You have to align both ends with each other.

Tips for Proper Driveshaft Phasing and Alignment - Power Test, LLC

Failure to phase and align a driveshaft properly will result in vibrations that will destroy the driveshaft, dyno, and/or engine.

powertestdyno.com