So i installed 2" drop shackles from auto zone on my NNBS RCSB 4x4 and now i have some vibrations. I can really notice it on deceleration between 20-30 mph but i also notice it throughout other speeds. From what i read, i should not have had any problems with vibrations from just 2" drop shackles on a rcsb. I did tighten the shackles with the tires off the ground but i cant really see that being the problem. So my only guess would be that i need some shims? Anyone have any problems like this? I will loosen and tighten the shackle bolts tomorrow to so if that helps, but if it does't go away what size shims do you recommend?

 

every truck can be different, even the same truck with the same parts

best bet is to measure your driveline angles and buy the appropriate shims

 

Yes, needing shims is common with drop shackles. As mentioned, measure the angles and get the right shims.

 

How do i go about measuring the pinion angles?

 

anyone?