Uh just guessin here BUT it came designed to shake?

All the time shake or just on accel or decel. What nearly put a giant hurt on my shortly after I bought my I/S I found out later-severe head shake on decel-was the upper shock bushings were toast. I replaced ALL 4 shock bushings and the difference were like night and day. Now when I do a rear end service shock bushings are changed out.
RIDE SAFE.