For the driveline vibration, driveline angle and driveline length are the 2 things I'd check first...
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For measuring the driveline angle.. Do you have an Iphone? If so, get the tremec driveline angle finder app. It will do the measuring for you.
As for the sway bar.. Well, while I don't run it, some people do and it does make a difference on road. Off-road it will make a difference too. There is no way I'd be able to get this kind of flex if I had my rear sway bar on. If your going to put it on, take it off when wheeling.
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Also, when I went SOA, I did have to stiffen up my rear shocks to make it ride better, otherwise it was leaning all over the place.. Enough to be annoying, especially the side to side sway I'd get on the 2 line blacktop near the house...
When they did your alignment, did they give you the specs of what it was and what it ended up with? What your looking for is thrust angle and caster. Those 2 things will cause pull.. Thrust angle means your rear axle isn't in straight and caster causes pull to the side with the least positive caster.
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I did have to pull the drive shaft a bit to get it to the axle flange, but never thought of that being the cause of the vibration....it's about 3/4"+ short and I've been trying to find a place that will do extensions before I really take it wheeling, but can't seem to find anyone. Also, while I have a Droid and not an iPhone, I was able to find the Tremec app and downloaded it.
But all that leads me to another question...the spring perches I purchased had three openings for the spring stud...if I moved the stud to the hole furthest back and not the middle, it would bring my axle and drive shaft closer so I wouldn't have to get the shaft extended, but how much would that effect my angles?
These are the perches I bought and installed, and here is a pic of both rear tires:
To me it seems like the wheels sit a little farther back than they used to...don't know why I didn't notice it until now. I think what I'll do is move the rear axle forward, use that handy app, test drive and report back...
I added the damper back on last night when I got back and took it for another spin...seemed to help a little bit.
I'm also thinking that if I throw the rear sway bar back on (adding disconnects of course), I'll have to relocate the shock mounts to the plates that are now on top of the springs...I'm assuming this will effect flex, but wasn't sure by how much...
It looks really bad now that I look at it again, but like I mentioned, I ordered the Skyjacker arm and should have it in Thursday night; I'll have the shop check my home-done toe alignment quick after they install the new tires when I go pick them up Friday...I did not get the specs from the shop on what I was at and what I ended up at as far as degrees of camber and caster, but I'll ask when they have it on the rack...you said awhile ago 2-5 degrees of caster is what I should have correct?
