Tuff Country 16990 - GM 2001-06 HD 3500 6 kit User Manual
Page 4
 
Please follow instructions carefully:
Before installation begins, measure from the center 
of the hub, to the bottom of the fender well, and 
record measurements below. 
 
Pre-installation measurements: 
 
Driver side front:______________________________ 
Passenger side front:__________________________ 
Driver side rear:______________________________ 
Passenger side rear:__________________________ 
 
At the end of the installation, take the same 
measurements and compare to the pre-installation 
measurements. 
 
Post-installation measurements: 
 
Driver side front:______________________________ 
Passenger side front:__________________________ 
Driver side rear:______________________________ 
Passenger side rear:__________________________ 
 
1. To begin installation, block the rear tires of the vehicle 
so that the vehicle is stable and can’t roll backwards. 
Safely lift the front of the vehicle, and support the frame 
with a pair of jack stands. Place a jack stand on both the 
driver and passenger side. Next, remove the tires and 
wheels from both sides. 
 
2. Remove the stock front upper and lower skid plates. 
The stock lower skid plate and stock hardware may be 
discarded. Save the stock upper skid plate and the (3) 
stock upper bolts for later re-installation. 
 
3. Remove the stock front driveline from the stock 
location on the front differential and the transmission. 
Save the stock driveline and hardware for later re-
installation. 
 
4. Working on the driver side, remove the stock hardware 
on the top of the stock shock. The upper stock hardware 
may be discarded. Remove the stock hardware on the 
lower shock mount and save the stock hardware for later 
re-installation. The stock shock may be discarded. 
Special note: New longer front 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 23” fully extended nitrogen gas shock. 
Repeat procedure on the passenger side. 
 
5. Measure the exposed threads on the torsion bar 
adjustment bolt and record measurement here for a later 
reference. 
Record driver side measurement here:______________ 
Record passenger side measurement here:__________ 
Photo # 1
6. Working on the driver side, attach the torsion bar 
removing tool to the stock torsion bar cross member, 
making sure that the unloading bolt in the center of the 
torsion bar removing tool is in the small divot of the stock 
torsion bar key. Adjust the torsion bar key up high 
enough so that the stock small metal adjusting block and 
bolt can be removed. Set the stock torsion bar block and 
hardware a side for later re-installation. Repeat 
procedure on passenger side. 
 
7. Mark both torsion bars before removal so that they can 
be re-installed back into the same location. Example: 
driver vs. passenger and front vs. rear. Tap the stock 
torsion bars forward until the stock torsion bar cross 
member can be removed. Once you tap the stock torsion 
bar out of the stock torsion bar cross member, the stock 
torsion bar key will fall out. Set the stock torsion bar key a 
side for later re-installation. Repeat procedure on the 
passenger side. 
 
8. Working on the driver side, remove the stock hardware 
that connects the stock torsion bar cross member to the 
stock mounting point. Set the stock hardware a side for 
later re-installation. Special note: The stock mounting 
point is on the inside of the stock frame rail. Repeat 
procedure on the passenger side. Remove the stock 
torsion bar cross member from the stock location and set 
a side for later re-installation. 
 
9. Working on the driver side, slide the stock torsion bar 
out of the stock rear lower control arm and set a side for 
later re-installation. Repeat procedure on passenger side. 
 
10. Working on the driver side, remove the stock sway 
bar end link from the stock location and discard the stock 
end link and all the stock hardware. Repeat procedure on 
the passenger side. Special note: At this time, invert 
the stock sway bar. 
 
11. Working on the driver side, remove the stock nut that 
connects the stock outer tie rod ball joint to the stock 
steering knuckle. Set the stock nut a side for later re-
installation. Carefully break the stock taper on the stock 
outer tie rod ball joint and remove the stock outer tie rod 
from the stock knuckle. Special note: Take special care 
not to rip or tear the stock outer tie rod ball joint dust 
boot. 
 
12. Working on the driver side, remove the stock brake 
line bracket that connects to the stock steering knuckle 
and discard the stock hardware. Next, remove the stock 
brake line mounting point that connects to the stock 
upper control arm. Save the stock hardware for later re-
installation. Also, remove any other brake line mounting 
points on the stock steering knuckle and stock upper 
control arm. 
 
13. Working on the driver side, locate the ABS line quick 
disconnect located above the stock upper control arm.