Chevrolet 1980 Light Duty Truck Service Manual page 300

3D-6 REAR SUSPENSION
Fig. 3D-16--Rear SPring Installation - G MOdels (Cutaway
Vans)
3. Jack frame as required to align spring and shackle
with spring hangers.
4. Install shackle bolt and nut and again reposition
spring, if necessary to align front eye. Install front eye bolt
and nut. Torque hanger and shackle nuts to specifications.
Make certain that the bolts are free-turning in their
bushings prior to torquing.
5. Lower vehicle so that weight of vehicle is on
suspension components and torque U-bolt nuts to
specifications.
6. Lower vehicle and remove from hoist.
U-Bolt and Anchor Plate Installation
Fig. 3D-23 illustrates the mandatory sequence of
tightening U-bolt nuts. Tighten diagonally opposite nuts to
40-50 foot pounds, then tighten all nuts as shown to
specifications.
NOTICE: See NOTICE on page 1 of this section,
regarding "U"-Bolt fasteners.
SHACKLE REPLACEMENT
1. Raise vehicle on hoist. Place adjustable lifting
device under axle.
2. Remove load from spring by jacking frame.
3. Loosen spring-to-shackle retaining bolt, but do not
remove.
4. Remove shackle-to-frame bracket retaining bolt
then remove shackle bolt from spring eye.
5. Position shackle to spring eye and loosely install
retaining bolt. Do not torque retaining bolt at this time.
6. Position shackle to frame bracket and install
retaining bolt. Arrow stamped on shackle must point
forward.
7. Rest vehicle weight on suspension components and
torque both shackle bolt retaining nuts to specifications.
NOTICE: See NOTICE on page 1 of this section,
regarding these fasteners.
8. Lower vehicle and remove from hoist.
LIG H T T R U C K S ER V IC E M ANUAL