To remove the 1999 Deville model, start by loosening the rear wheel lug nuts and blocking the front wheels. Then, raise the rear of the vehicle and support it securely on jackstands placed under the frame. Remove the rear wheels. If you're removing the left-side coil spring, detach the ELC height sensor link from the control arm. Install a suitable interior-style spring compressor through the bottom of the control arm and onto the coil spring, compressing it enough to relieve all pressure from the spring seats. Detach the rear stabilizer bar link from the control arm and the lower end of the shock absorber from the control arm, as well as the airline from the shock absorber. Place a floor jack under the inside edge of the control arm to support it. Paint alignment marks to indicate the position of the coil spring pigtail in the insulator slot. Remove the control arm pivot bolts and detach the control arm from the frame crossmember. Slowly lower the jack and remove the spring and insulators, carefully removing the spring compressor from the spring. For installation, replace any damaged or worn insulators and position them correctly in the control arm and upper body. Before tightening the control arm pivot bolts, raise the outer end of the control arm to simulate normal ride height. Tighten all suspension fasteners to the torque specifications and the wheel lug nuts as well. For the 2000 and later Deville/DTS models and all Seville models, the removal process is slightly different. Loosen the rear wheel lug nuts, raise the rear of the vehicle, and support it securely on jackstands. Block the front wheels and remove the rear wheel. Detach the stabilizer bar link from the control arm and support the lower control arm with a floor jack placed under the end of the control arm. Detach the shock absorber from the control arm and the toe link from the control arm. Slowly lower the floor jack until the control arm comes to rest against the suspension support, and then remove the coil spring. For installation, make sure the insulator is in place on the control arm when installing the coil spring. Ensure that the pigtail at the upper end of the spring is pointing to the rear for the left coil spring and forward for the right coil spring. Tighten all suspension fasteners to the torque specifications and the wheel lug nuts as well.
