GM Full-Size Trucks 1970-1979 Repair Guide
REMOVAL & INSTALLATION
Raise and safely support the vehicle so that all tension is taken off of the front suspension.
Remove the shackle upper retaining bolt and the front spring eye bolt.
Remove the spring-to-axle U-bolt nuts. Pull of the spring, the lower plate, and the spring pads.
Remove the shackle-to-spring bolt, bushings, and shackle.
To replace the bushing, place the spring in a press or vise and press out the bushing. Press in the new bushing. The new bushing should protrude evenly on both sides of the spring.
Installation is the reverse of removal. The following tightening specifications are necessary:
U-bolts: 1970-72 vehicles to 120 ft. lbs. (163 Nm) and 1973-79 vehicles to 150 ft. lbs. (203 Nm)
Spring shackle: 50 ft. lbs. (68 Nm)
Front eye bolt 90 ft. lbs. (122 Nm)
Rear eye bolt 50 ft. lbs. (68 Nm)