Final Assembly - Chevrolet 1988 Light Duty Truck Repair Manual

OUTPUT SHAFT SHIM SELECTION
• Refer to figures 1 through 4.
• It is necessary to select the proper size output shaft
shim (20) if any of the following com ponents were
replaced.
— Shaft (1).
— Tube (5).
— Output shaft (23).
— C arrier case (29).
— Ring and pinion gears (37).
— Differential case (35).
— Bearings (33).
— C arrier connector (9) (K15-25 models).
Preferred Method:
Tool Required:
J 34672 Depth Gage (or equivalent)
1. Refer to figures 37 and 38.
2. Push on the inner end of the shaft (1), and move the
shaft outboard as far as it will go. The shaft must be
in this position when m easuring dim ension " A" .
3. Measure dim ension " A" . Use J 34672 or equivalent
(figure 38).
• K15-25: Tube flange m achined surface to inner
surface of connector (9).
• K35: Tube flange machined surface to inner
surface of axle shaft shoulder.
4. Measure dim ension " B."
• Carrier machined surface to outer surface of
output shaft (23).
5. Subtract dim ension " A" from dim ension " B."
6. The correct shim size will be one size sm aller than
the figure obtained in step 5. Examples:
• If the figure obtained in step 5 was 3.53 mm,
use a 3.30 mm shim.
• If the figure obtained in step 5 was 3.30 mm,
use a 2.70 mm shim (K15-25 models) or 2.80
mm shim (K35 models).
7. Shim s are available in the following sizes:
• K15-25 models: 1.27 mm 1.78 mm, 2.29 mm,
2.70 mm, 3.30 mm, 3.81 mm.
• K35 models: 1.80 mm, 2.30 mm, 2.80 mm, 3.30
mm, 3.80 mm, 4.30 mm, 4.80 mm.
Alternate Method
Use ONLY if proper tools for calculating the shim size
0
are not available.
Install or C o n n ect (F ig u res 1 th ro u g h 4)
1. Original shim (20) to the shaft (1). Use grease to
hold it in place.
2. Assem bled axle tube and shaft to the carrier. Use no
sealer at this time.
3. Bolts (6). Tighten to 40 N m (30 ft. lbs.).
M easu re (F ig u re 39)
Tool Required:
J 8001 Dial Indicator (or equivalent)
Shaft (1) end play.
1. Install a dial indicator (J 8001 or equivalent) on
the axle tube end. The plunger of the indicator
must be at a right angle to the axle flange
(figure 39).
K TRUCK FRONT AXLE 4C4-17
2. Move the shaft (1) back and forth and read the
end play. Correct end play is 0.03-0.51 mm
(0.001-0.020-inch).
3. If end play is incorrect, install a thicker or
thinner shim as needed to bring end play into
the specified range.
R em ove or D isco n n ect (F ig u re s 1 th ro u g h 4)
1. Bolts (6).
2. Axle tube assembly.

FINAL ASSEMBLY

JQ® Clean (F ig u res 1 th ro u g h 4)
• S e a lin g s u rfa c e s of th e tu b e (5) and c a rrie r
a s s e m b ly . R e m o v e a ll o il a n d g re a s e .
carburetor cleaner or equivalent.
-►*- Install or C o n n e c t (F ig u res 1 th ro u g h 4)
Shim (20), as selected previously, to the output shaft
1
.
(23). Use grease to hold it in place.
Shift fork (18), shaft (17), sleeve (22), and spring (16)
to the carrier case.
Apply a bead of sealer (GM part no. 1052942
[Loctite 518] or equivalent) to the tube (5) sealing
surface.
Assembled tube (5) to the carrier assembly.
Bolts (6).
T ig h ten
Bolts (6) to 40 N-m (30 ft. lbs.).
1? In sp ect (F ig u re 40)
• Shift m echanism operation. Insert a drift into
the actuator hole in the axle tube. Rotate the
axle flange while moving the shift fork with the
d rift. T he s h ift m e c h a n is m s h o u ld w o rk
smoothly, w ithout bind.
5. Solenoid (10). Apply sealer (GM part no. 1052942
[Loctite 518] or equivalent) to the threads. Tighten to
22 N-m (16 ft. lbs.).
6. Switch (13). A pply sealer (GM part no. 1052942
[Loctite 518] or equivalent) to the threads. Tighten to
5.0 N-m (45 in. lbs.).
7. Axle lubricant, as specified in the proper Truck
Service Manual.
8. Drain and fill plugs (25) with sealing washers (26).
Tighten to 33 N m (24 ft. lbs.).
U se