My local shop put some 2" rear lowering shackles on my 2005 Screw. Between 24-29mph and 56-70mph I now have vibration. It also vibrates right before I come to a stop. They contacted Belltech and they told them that the change in the pinion angle after lowering it 2" can cause vibration. Belltech sent some 3" shims which helped the problem about 70%. The local shop which is experienced and reputable stated that they have not had this problem before except when lifting not lowering. I love the level look but I don't know if I can live with the minor vibration. I am **** and only focus on that damn vibration now. Anyone have the same problem? If not what brand did you use. Mine is a 4x2 with stock 18" rims and tires. Thanks.

 

I used the belltechs on my 02 reg. cab without shims and had no problems, but 3 deg. shims seems like too much you probably need 2 deg. shims. On my 07 screw I have the groundforce shackles and use a 2 deg. shim and have no problems.

 

Yes, you need 2 degree shims. The Ground Force kit comes with 2 degree shims.

 

I'll try the 2" shims. Hopefully that will get rid of that vibration. Thanks for the input.

 

I meant 2 degree...just woke up