Tuff Country 16830 - GM 92-98 K1500 Suburban and 2-door Tahoe 6 kit User 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