Lifting woes......anybody an engineer??? :(
 

Installed a 3" series 2 lift from Rough country.......had vibes......dealt with them for a while....then went and installed the RE h&t. had different vibes...not real noticeable like beforehand....just could feel a buzzz if you will.
research showed me..my rig may require shims, stuck in 1" spacers/block for an upcoming mtn trip that I cannot miss...and can't afford better rear support at the moment....So, I'm pretty much sittin on 4" now....now Rough Country tells me they install 6* shims on the spring pack....put my trusty angle finder to the rear yoke....and did the socket method and each gave me a reading of 10 degrees...went up and down the underside of the driveshaft..got a reading of 15*....so if I already have 6* shims....the largest shims i've heard of are 8*which would put me 3* low..which might be bearable, I'm not sure.....
Where do I go from here?????..I've heard shackle lifts help......but how much???
In closin.....is this the greatest extent my 98 can go in height???? I was considering a 6 1/2 LA from rough country next spring...but am kinda skeptical if my drivetrain will even tolerate such a lift.....
any suggestions would be greatly appreciated......
Scott

bump

The 6 degrees is more of a rule of thumb. The more important rule of thumb: point the pinion at the tcase output. You'll have to try different setups to see what gets rid of the vibes. Sounds like you are already trying the right things. Your lifting blocks may be slightly angled as well (if so, make sure they're both in the same way, heh).

Are the vibes constant, or do they come while accelerating, or coasting? I think the real problem people have with blocks (if they take the time to explain themselves instead of being judgmental) is that they increase axle/spring wrap, which increases driveline problems from angles and runout. 1" should be fine, though, and imo is a fine way to make a balanced upgrade. You can also have your blocks machined to exactly the angle you want, which is something I plan to do when I settle on my rear spring setup.