
7–18
Copyright © 1996 General Motors Corp.
AT 500, 1500 SERIES AUTOMATIC TRANSMISSIONS
7–12. REMOVAL OF TRANSMISSION
FROM OVERHAUL STAND AND
INSTALLATION OF EXTERNAL
COMPONENTS
a.
Supporting Transmission
(1) Attach a sling to the transmission. Sup-
port the transmission and remove it from the holding
fixture.
(2) Remove adapter J 23642-01 (Figure 7–39).
Lower the transmission to a supporting surface, and re-
move the sling.
NOTE:
•
For models with retarder, proceed with Para-
graphs 7–12b and 7–12c.
•
For models without retarder, skip Paragraphs
7–12b and 7–12c, and proceed with Paragraph
7–12d.
b.
Determining Third Clutch Clearance
(1)
Using third clutch clearance gauge
J 23716, enter through the retarder valve body (PTO
pad) opening to access the third clutch pack, and
check the running clearance. The thin end of the gauge
should pass between the retarder housing and the first
clutch plate; the thick end should not. The running
clearance is correct with a dimension of 0.028–0.119
inch (0.74–3.02 mm).
(2) If clearance is excessive (larger end of
gauge enters plates), rebuild the transmission to the
area of the third clutch and replace worn plates with
new plates. Refer to the wear limits in Section 8 for
clutch plate dimensions.
(3) When third clutch clearance is proper,
proceed with Paragraph 7–12c.
c.
Installing Retarder Valve Body
(1) Lay retarder control valve assembly 18
(Foldout 13) on the work table, outside surface down-
ward.
(2) Put one gasket 16, separator plate 17, and
a second gasket 16 in place on retarder control valve
assembly 18.
(3) Put transfer plate assembly 6 in place on
gasket 24 and carefully install four
1
⁄
4
-20 x 1
1
⁄
4
inch
bolts 4 and flat washers 5, aligning the parts. Using
preset torque wrench J 29612, tighten bolts 4 to 8–12
lb ft (10–16 N.m).
(4) Through the retarder valve body (PTO)
pad opening, install two jumper tubes 2 into their
bores in the retarder housing.
(5) Install gasket 1 and complete retarder valve
body assembly 3, retaining them with four
3
⁄
8
-16 x 4
1
⁄
4
inch bolts 36. Tighten the bolts to 26–32 lb ft (36–
43 N.m).
(6) Skip Paragraph 7–12d and proceed with
Paragraph 7–12e.
d.
Installing PTO Cover (Foldout 12,A)
NOTE:
If the PTO is to be installed right away, skip Steps
(1) and (2) and proceed with Paragraph 7–12e.
(1) Install gasket 1 and cover 2.
(2) Retain the cover with six
3
⁄
8
-16 x
3
⁄
4
inch
bolts 3. Tighten bolts 3 to 15–20 lb ft (20–27 N·m).
e.
Installing Neutral Start Switch,
Speedometer Components
(1) If not previously installed, install neu-
tral start switch or plug with socket wrench J 33410
using partial turns of the wrench. Tighten the switch
to 50–60 lb ft (68–81 N·m) or, tighten the plug to
24–45 lb ft (33–60 N·m). Make sure the tool is not
contacting the transmission housing when verifying
final torque reading.
(2) Install speedometer driven gear assem-
bly or plug, as required. Tighten locking nut or plug
to 45–50 lb ft (61–68 N·m).
f.
Shift Lever Installation. Refer to Paragraph
3–12 for installation specifications.