Tuff Country 16810 - GM 88-98 K1500 / K2500 6 lug 6 kit - Manual (Page 6)

34. Working on the driver side, remove the stock
hardware that connects the upper driver side tab of the
stock front differential to the stock location. Save the
stock hardware for later re-installation.
35. Working on the passenger side, remove the (2) stock
nuts that connect the passenger side of the stock front
differential to the stock location and save the stock
hardware for later re-installation.
36. Carefully lower down on both hydraulic floor jacks at
the same allowing enough room to remove the front
differential completely from the vehicle. Remove the front
differential completely from underneath the vehicle.
37. Working on the driver side of the stock front
differential upper tab, measure 2” from the stock
mounting point and scribe a mark on the front differential.
Using a sawzall, carefully cut the upper tab off of the
stock front differential and discard. Refer to illustration #
6 for proper cut line. Take special care not to cut into
the stock front differential housing.
See Illustration # 6
38. Locate the new driver side differential relocation
bracket, (1) 7/16” X 3” bolt, (1) 7/16” unitorque nut, (2)
7/16” flat washers and (1) 7/16” lock washer from
hardware bag 16810NB2. Also, locate (2) PB2408G poly
bushings and (1) 9/16” x 2 1/8” anti crush sleeve from
hardware bag 16810SL. Install the new poly bushings
and anti crush sleeve into the new driver side relocation
bracket. Special Note: Make sure to use a lithium or
moly base grease prior to inserting the new bushings
into the new driver side differential relocation
bracket. This will increase the life of the bushing as
well as prevent squeaking. Referring to illustration # 7,
remove the (4) stock differential mounting bolts that
connect to two half’s of the front differential together.
Save the stock hardware for later re-installation. Secure
the new driver side differential relocation bracket to the
stock front differential using the stock hardware that was
removed earlier in this step. Special Note: Get all (4)
stock bolts started but do not tighten at this point.
Also, make sure to use thread locker or lock tite.
Secure the lower portion of the new driver side
differential relocation bracket to the stock front
differential, using the new 7/16” x 3” bolt and hardware.
Torque to 34 Ft. lbs. Go back to the (4) stock bolts that
hold the new differential relocation bracket to the stock
front differential and torque to 34 ft lbs. Special Note:
Make sure not to over tighten the stock and new
hardware associated with the front differential. If
bolts are over tighten, the stock front differential
may crack.
See Illustration # 7
39. Locate the new passenger side differential drop
bracket and the stock hardware that was removed from
step # 35. Install the new passenger side differential drop
bracket into the stock upper location and secure using
the stock hardware. Do not tighten at this point.
Special Note: Make sure to use thread locker or lock
tite.
See Illustration # 8
40. Locate (2) 9/16” x 1 3/4” bolts, (4) 9/16” flat washers,
(2) 9/16” unitorque nuts and (2) 9/16” lock washers from
hardware bag 16810NB4. Carefully raise up on both
hydraulic floor jacks at the same time until the passenger
side of the stock front differential sits flush with the newly
installed passenger side differential drop bracket. Install
the passenger side of the stock front differential to the
previously installed passenger side differential drop
bracket. Secure using the new 9/16” x 1 3/4” bolts and
hardware. Do not tighten at this point. Also, make
sure to use thread locker or lock tite. Using a bungee
cord, carefully tie the driver side of the stock front
differential up and out of the way so that the new one
piece lower sub frame can be installed. Also, at this
time re-connect the 4WD wiring harness back into the
stock location on the stock front differential.
See Illustration # 9
41. Carefully remove both hydraulic floor jacks from
under the stock front differential.
42
. Locate the new one-piece lower sub frame and the
stock lower control arm hardware that was removed in
step # 28. Working on the driver side, install the front and
rear part of the new one piece lower sub frame into the
stock front and rear lower control arm stock pockets and
secure using stock hardware. Do not tighten at this
point. Make sure to use thread locker or lock tite.
Repeat procedure on passenger side.
See Illustration # 10 / Front Location
See Illustration # 11 / Rear Location
43. Carefully remove the bungee cord that is holding the
driver side of the front differential up and out of the way.
Let the stock front differential rest on the newly installed
one piece lower sub frame.
44. Locate the stock rear driver side differential mounting
bracket hardware that was removed from step # 30.
Install the rear portion of the front differential into the tab
on the rear portion of the new one piece lower sub frame.
Secure using the stock hardware. Do not tighten at this
point. Make sure to use thread locker or lock tite.
Special Note: During this procedure the front
differential is being lower in relation to the frame. On
some I.F.S vehicles this can cause a clearance
problem between the cooling fins on the stock front
differential and the stock rear lower control arm
pocket. If contact occurs, it may cause binding and
damage to the differential housing. The differential
also must be centered to allow the proper amount of
inner CV joint plunge. When the cooling fins contact
the frame, the differential is pushed to the passenger
side. This causes the left axle to over extend causing
the inner CV joint to pull out of the housing. When