I recently picked up an 06' Screw King Ranch with 89,000 miles on it. It seems like when I hit a large bump or hole (especially if the wheels are turned) that I get kind of chatter in the suspension all the way back. If I am going fast enough it is almost the same as if I were fish tailing on ice. I had an 02' King Ranch before this one with 190,000 miles (stolen out of my drive way, it’s why I got me another) with OEM shocks still on it. I have noticed that this truck has already had some after market Ranchos installed. My mechanic says he thinks it needs new shocks and wants roughly $800 installed for the OEM shocks. Tires are balanced with about half tread life left and no alignment issues. Any suggestions???