Vehicle rear leaf springs are one of the parts that make up the suspension system of a car. They are made to enhance on and off road performance, handling, and control. Thus failing to take care of such part can jeopardize the safety of the car and its occupants. After aligning a car leaf spring, ensure that the car is safe and controllable. This, however, should not be performed on public or busy roads.
Step 1 – Jack up the Vehicle
For best results for your vehicle park in a spacious and flat surface; ensure there is enough space to work at the vehicle’s rear. Carefully jack the vehicle up and place it on stands. It is advisable that you put the vehicle in neutral with the parking brake off.
Step 2 – Remove and Check the Leaf Spring
Keep one jack stand three to four inches from the end of the leaf spring, being careful not to lift the vehicle too high. Use a wrench to loosen the bolts and remove the rear spring bolt from the trailing arm and spring. Carefully lower the jack to ease the pressure on the spring. Then remove the four rear spring center plate bolts using a wrench. Remove the springs and put on a clean surface.
Inspect the condition of the leaf springs; looking for damage, wear and tear. If they are damaged, change them with new ones.
Step 3 – Reinstall, Align and Adjust Leaf Spring
Reinstall the leaf springs and make sure the bolts are fitted firm. Measure the height of the car from the ground to the mid section of the vehicle. Ensure the vehicle is on a flat surface. Compare the results with the vehicle’s service manual. Bounce the car up and down at the corners to stabilize the suspension before checking the vehicle’s height.
Measure the height of the car at four points, the ground clearance of the; front wheel, adjustment cam bolt center at the front, rear wheel center, and rear leaf spring front side bushing center.
Step 4 – Adjust the Toe In
Confirm if the toe-in is within the specified range as advised by manufacturers. Ideally it should stay in the middle of the specified range. Take out the rack boot set clips. Use a wrench to loosen the tie rod end lock nuts. To adjust toe-in, carefully turn the right and left rack ends.
Besure that the lengths of the right and left rack ends stay same. Fasten the tie rod end lock nuts and be careful not to use too much force. Change the boots on the seats and reinstall the clips.
Step 5 – Check Wheel Turn Angle
Inspect that the right and left turning angles of the inside and outside wheels are within the required ranges. To check wheel turn angle, inspect the right and left rack end lengths for all wheels and ensure they are within the range specified by the manufacturer.
Complete alignment by checking the camber, caster, and steering axis inclination. To re-adjust the camber and the caster, loosen the nut and bolt with the use of a wrench and turn the camber adjust cam and toe adjust cam to make the adjustment. Normally the camber and caster should be adjusted to their normal central values.