Rear driveshaft wrong angle after new leaf pack

Just installed the general spring HD spring pack and got maybe 2" of lift.
After driving it around a bit, there's a minor driveshaft vibration with throttle.

It kinda seems like the axle is twisted a bit. Shims to fix? Or is that normal?

 

Did the springs come with a degreed shim? If not you can drop the carrier bearing with shim several out there. Those are two places to start.

 

No shim with the leaf pack.
If the problem lies in the rear-most driveshaft section, then just correcting the angle at which that section goes into the axle would potentially solve the problem?

 

Whenever you lift the rear end up, the angles at the u joints change and need to be returned to as close to possible where they where. Usually a 2-3 degree shim under the pack helps this but since your pack didn’t come with one you can try dropping the carrier a 1/2” somethings you may need both. Even doing this you may not get rid of all the vibration.

 

You need 3 degree shims.

 

To rotate the axle pinion up or down?

 

pinion up

 

Just put 2-3 washers under both bolts on the center support. Also as your tightening it push it to the drivers side. That should fix the problem.
Drive around see if it is better then add or remove for the best feel.


Shimming the axle will only work when the center ujoint is replaced with a double cardon joint.

 

After driving around for a while I have the symptoms nailed down. It seems to be way less of a problem compared to other vibes people experience.

I only get a shudder accelerating in 1st around 5 mph, and a smaller shudder in 2nd, accelerating up to 10 mph with maybe 1/4 throttle. Any less throttle and theres no shudder at all. Any MORE throttle and there also is ZERO shudder. I've had the truck up to 80mph and its all smooth up there...
I read a couple places theres not much you can do about the shudders at low speed, so am I just stuck with it?

 

You can try fine tuning with thinner washers. Did you push it over to drivers side before tightening? that also helps.

 

I haven't done anything to it yet. I wanted to wait until the springs settled down. Have about 400 miles on them now.

But now would be a good time to shim the CB I guess.
The shudder isn't super bad by any means.