Tuff Country 14721 - GM 73-87 3/4 ton 4 box kit (systems with rear springs) - Manual (Page 5)

to the rear differential housing using the stock bolt.
Special Note: Make sure to use thread locker or lock
tite. Next, attach the stock brake line bracket to the
newly installed brake line bracket and secure using the
new 5/16” x 1” bolt and hardware. Torque to 16 ft. lbs.
See Illustration # 7
24. Position a pair of hydraulic floor jacks under the rear
axle. Place one jack stand on the driver side and one on
the passenger side. Raise up on both hydraulic floor
jacks at the same time until they make contact with the
rear axle.
25. Working on the driver side, remove the stock shock
and save the stock hardware for later re-installation.
Special Note: New longer rear shocks are needed, if
you have not already ordered shocks, please contact
Tuff Country or your local Tuff Country dealer and
order the proper shocks. Tuff Country recommends
using a 26” fully extended nitrogen gas shock when
installing a 2” or 3” suspension system and a 30”
fully extended nitrogen gas shock when installing a
4” suspension system. Repeat procedure on the
passenger side.
26. Working on the driver side, remove the (2) stock rear
U-bolts and discard. Set the upper U-bolt plate a side for
later re-installation. Repeat procedure on passenger side
27. Lower down on both hydraulic floor jacks at the same
time until the stock springs separate from the stock rear
axle. Lower down approximately 5”. Special Note: Make
sure not to over extended any brake lines or hoses
when lowering the axle. This will allow you enough
room for the new rear springs to be installed.
28. Working on the driver side. Remove the stock spring
from the stock location. The stock spring and stock
spring eye hardware may be discarded. Repeat
procedure on the passenger side.
29. Locate the new rear springs and the new rear spring
eye hardware. Working on the driver side, install the new
rear spring into the stock location and secure using the
new spring eye hardware. Make sure to use thread
locker or locktite on these bolts. Torque the rear
spring eye hanger hardware to 120 ft lbs. Special Note:
Do not torque the rear spring eye shackle hardware
at this time. Once the vehicle is lowered to the
ground, the rear spring eye shackle will be torque to
40 ft lbs. Repeat procedure on the passenger side.
Special Note: The new rear springs have an off set
centering bolt, the longer end of the spring needs to
be installed towards the rear of the vehicle.
30. Carefully raise up on both hydraulic floor jacks at the
same time until the newly installed rear springs seat
properly to the stock rear spring perches.
31. Locate (2) new 5/8” x 3 1/2” x 9 5/8” Round U-bolts,
(4) 5/8” U-bolt High Nuts and (4) 5/8” U-bolt Washers.
Working on the driver side, install (2) new 5/8” x 3 1/2” x
9 5/8” round U-bolts into the stock location and secure
using the new 5/8” high nuts and washers. Torque to
130 ft lbs. Repeat procedure on passenger side.
Special Note: With a suitable cutting tool, cut off the
excess U-bolt threads on all (4) rear U-bolts.
See Illustration # 8
32. Working on the driver side, install the new rear
shocks absorbers using the stock hardware removed
from step # 25. Special Note: New longer rear shocks
are needed, if you have not already ordered shocks,
please contact Tuff Country or your local Tuff
Country dealer and order the proper shocks. Tuff
Country recommends using a 26” fully extended
nitrogen gas shock when installing a 2” or 3”
suspension system and a 30” fully extended
nitrogen gas shock when installing a 4” suspension
system. Repeat procedure on the passenger side.
See Illustration # 8
33. Check and double check to make sure that all step
related with the front and rear end were performed
properly. Check and double check to make sure that all
stock and new hardware is torque to proper torque
specifications. Use the torque sheet at the beginning of
the installation manual.
34. Install the tires and wheels and safely lower the
vehicle to the ground.
35. With the weight of the vehicle on the ground, torque
the top and bottom spring eye shackle bolts on the driver
and passenger side to 40 ft lbs.
36. Once the installation is complete, make sure to bleed
the brake lines. Also, using the proper brake fluid, make
sure to top off the brake fluid level.
CONGRATULATIONS INSTALLATION
COMPLETE
Special Note: After the completion of the
installation, Tuff Country EZ-Ride
Suspension recommends taking the vehicle
to an alignment shop and having a proper
front end alignment performed.
It is also a good idea to keep a close watch
on the front and rear drive line U-joints. If
they start to wear out, make sure to replace
them.
If you have any questions or concerns,
please feel free to contact Tuff Country or
your local Tuff Country dealer.