Even though most people don't, it is a good idea to check the pinion angle after installing rear springs like the super stock springs that change the ride height of the rear of the car.
The correct pinion angle should be between 5 and 7 degrees downward angle (nose of the differential pointed down towards the ground) and can be measured several ways, The measurement should be done with the vehicle sitting on all four wheels and with a full tank of gas. The easiest way to measure the angle is with a protractor that has a long arm on it. You place the base of the protractor on the flange of the differential yoke and then move the arm so it is parallel with the driveshaft and that reading is your angle. If needed, you can change the pinion angle by purchasing rear axle shims from Mopar Performance that come in pairs of 1, 2, & 3 degrees and placing them between the spring perch on the axle housing and the spring.
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