What control arms did you buy? And as I found out from another trusted source the uppers should be left OEM, just replace the bushings. Reason being the aftermarket uppers with their stiff bushings cause so much strain to the torque box that it can not hande that kind of stress and causes the torque boxes to break away. You can buy a torque box reinforcement kit for using new aftermarket UCA. If you go with a torque arm and pan hard bar, then you can get rid of the uppers all together.
What was the reason for the new control arms prior to this? And please give a better explaination of what you are experiencing with the rearend.
2015 Race Red Performance Package GT 5.0 (435hp) stock
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