All this talk about tcases exploding has got me questioning my pinion angles.
Just looking for some opinions/comments regarding my pinion angles in the attached pictures.

The little details:
-07 JK Unlimited Rubicon
-AEV4.5" lift w/ca drop brackets
-non-adjustable oem arms
-5.13 gears
-RE1310 front&rear driveshafts
-37" tires
All the above has been on for just over a year and no signs of stress on the tcase yet,no failed u-joints.

I do feel a slight oscillation between 80-100kmh(above and below that I don't feel it). It's not a constant oscillation but repeating with a pause if that makes sense.

Thanks in advance for feedback.

 

the rear pinion angle looks ok but the front dont

 

You have brackets, there is nothing you can do to change the angles short of tossing them in the trash and adding adjustables...

Pic 4 - looks really good
Pics 1/2 - I would want to play with that angle a bit, maybe go with a little less caster. It doesn't look like a horrible angle, but my guess is that this is where your oscillation is coming from.

 

Last week I was playing with the same issue, and at the same speeds I had the ocsaliation (sp?) as well. My front pinion angle was at 9 degrees. I adjusted it to about 1 or 2 degrees and I no longer hear the noise. I figured it was my front DS by taking it off and jumping on the highway. A pair of adjustable control arms would be an easy fix.

I am running 5.5in lift, 5.38 gears, 1350 D/S, and 37in tires.

 

Your rear angle looks good. For the front it is a compromise between drivability and front driveline vibration. You make this adjustment by changing the length of your control arms to adjust your castor setting. Factory castor is +4.2 degrees. Using a setting of +4.2 will minimize your drive line vibration, but will result in "flighty steering". Running a castor angle of +6 degrees will result in really nice steering feel, but you will have some driveline vibration. Start with a castor setting of +4.2 and go for a drive. Then slowly increase your castor angle until you reach a point where you have acceptable steering and minimize your vibration. I ran +4.2 for awhile after cracking my front Tcase housing, but I've slowly increased that to my current setting which is +5.5. I run a 4" FT lift.

I also remove my front DS for long road trips.

 

KenB, that would be good advice, except:

There is zero adjustability with the lift he chose.

All he can do is pull that driveshaft to verify that it is actually causing the vibes, and maybe see if it needs to be re-balanced or serviced.

 

i see cam bolts, which, according to the white line, looks like they have moved!!! 1st n 2nd pics...
remove them asap!
the rear angle looks good!

 

Good call, I totally missed that. Looks like you have them on both ends of the arms? Wonder what the angles were like before the cams went in? And did the oscillation start before or after they went in? And it looks like the one at the axle end slipped?

Personally, I'd trash both the brackets and the cams, have the holes from the cams welded back up, and then install adj's.

 

The cam bolts are gone. The other white line is a previous line before the cam bolts were removed and drop brackets put in so it actually hasn't moved according to the new line(my bad,should have scratched the old line off)


I honestly can't remember. You know, it's one of those things you don't start paying attention too until something catastrophic comes up like tcases exploding. If I had to take a guess I'd say I don't recall the vibe being there before the drop brackets were put on, just a guess though.

So, I guess to fix this I need to do the following:
1). Get front driveshaft serviced/balanced
2). If 1 does not fix problem, dump drop brackets and get adjustable LCA.

Agree?

 

I did that and the ds was in balance...he will most likely have similar findings and without the adjust ca he won't be able to do much. One thing is certain as both Ken and I know the OP's symptoms will lead to t-case explosion if not corrected. Get some control arms and follow what Ken says above.