i have the bell tech hangers only with the stock shackles and i still have the same 6 degree shim installed from the previous 4 inch drop. i have a small vibration with the stock shackles that i did not have with the bell techs installed . with the pinion angle being a little different, do i need a bigger shim or should this be fine with the lowering hangers and stock shackles?

 

Sounds like you may have too much negative angle. Do you have the vibration under trottle or decel?

You may want to go to a 3 or 4 deg shim....

You really should have a gauge put on it to be sure, you want 1-2 negative for best results.....

 

i was wondering if the 6 is not enough because with the stock shackles it brings the rear spring down so the pinion angle went up alittle in the front. it looks like i need a little more angle downward on the front , so would this need a thicker shim. it only vibrates when you accelerate really easy, if you get in it you dont feel it as bad .

 

Well if that is the case.... Yes you need more negative. If you get vibrations under throttle you dont have enuff, vibrations under decel mean you have to much. If I remember right JL has just hangers on his 99 and used 8 deg of shims to make it work right. Hope this helps....

BTW- the biggest shim I have seen is a 6deg one. I have two in my truck and its not reccommended, you just have to keep a eye on them to make sure they dont move out of place.

 

thanks for the info, i might just put the bell techs back on and raise my rear a little with the air bags i have for towing . it only raised it an inch without the shackles and i really dont want any more than one shim per side. with the bell tech shacles the pinion angle is perferct and with the bags pumped up it does not change the pinion angle at all, just stiffens the ride up a little.