Originally Posted by stikle
Well, I added 8 washers per side to drop the carrier bearing down a little bit, and I THINK it's better...but that might just be the placebo effect.
What's the corrective action if it's an incorrect pinion angle?
Dropping the carrier bearing does the same thing as "shimming" the rear axle, to a point
. As the carrier is lowered it detracts from the proper angle of the front half of the drive shaft while improving the rear angle. In cases where there is (very) minimal pinion angle error, dropping the carrier a tad, like you did, may provide symptomatic relief. It is just not the best over all solution.
The best use for dropping the carrier is to see if pinion angle is the source of a vibe (outside of actually measuring it), then correct the pinion angle with wedge shaped shims between the spring pack and the spring perch. Search the net for "pinion angle" and "pinion angle shims".
The perfect pinion angle for my springs is around a degree or two down from pointing directly at the carrier bearing. Under load, the rear will tend/try to rotate the pinion "up" (axle wrap) in reaction to the torque of the axles. In a perfect world the rear u-joint will then be at the theoretical strongest angle. Additionally, this slightly low angle will let the rear u-joint bearings move just enough to spread the wear a little and to help to distribute lube. The amount of shimming needed will vary from one spring design to another. There are "guidelines" to determine the required shim for a given lift but I hold to "just measure it and correct it".
Originally Posted by SeattleCoug
Would getting 32, or 33" tires change the angle of the CV joints much?
Not much if any from diameter. An increase in track width from a larger tire can effectively provide greater leverage through the LCA against the spring resulting in a slightly lower ride height.