GMC 1976 ZEO 6083 Maintenance Manual page 475

3. Position range selector lever in the neutral
detent position .
4. Tighten relay rod clamp screw to 20 ft. lbs.,
making sure shift lever is held against Neutral stop
while this operation is being performed.
5. Check operation of selector lever by perform-
ing the following steps :
a. Lift lever and move to Neutral detent .
(This is the detent in the transmission .) Release the
lever and check to make sure that the lever fits into
the neutral notch in the steering column.
b. Move lever to Drive detent . There should
be a slight travel of the lever beyond this detent until
the drive stop in the steering column is reached.
c. Move lever to Reverse detent and check as
in b above .
6. Check for proper operation of neutral safety
switch and back-up lights, (be sure vehicle has posi-
tive "PARK" engagement and "LO" range engage-
ment).
DOWNSHIFT SWITCH
ADJUSTMENT
The procedure for adjusting the downshift switch
is described in SECTION 6M under "Accelerator
Control" .
CHECKING AND ADDING FLUID
Oil Recommendations
Whenever fluid is added to the transmission use
only DEXRON ® II type transmission fluid, or
fluids of equivalent quality that have been especially
formulated and tested for use in the Turbo Hydra-
matic transmission .
Oil Level
NOTE:
Vehicle level and oil temperature are par-
ticularly important when checking fluid level on
a Turbo Hydra-matic transmission . Careful at-
tention to the following procedures is necessary
in order to determine the actual fluid level.
The transmission dipstick and filler tube are
located under the engine access cover at the left cen-
ter side of the engine . The "FULL" and "ADD"
dimple marks
on
the transmission dipstick indicate
6.
TRANSMISSION 7- 27
one pint difference. Correct fluid level is determined
at normal engine coolant operating temperature,
190-200°F. (88-93°C .). Automatic transmissions are
frequently overfilled because fluid level is checked
when the fluid is cold and dipstick indicates fluid
should be added. However, the low reading is normal
as proper fluid level at low operating temperature
will be below the "ADD" mark on the dipstick, as
shown in Figure 15, and proper fluid level at higher
operating temperatures will rise above the "FULL"
mark. Fluid level rises as the fluid temperature in-
creases. A fluid level change of over 3/4" will occur
as temperature rises 60"F . (15 .6°C.) to 190°F.
(88°C.).
Overfilling can cause foaming and loss of fluid
through the vent . Slippage and transmission failure
can result .
Fluid level too low can cause slipping, particu-
larly when the transmission is cold or the vehicle is
on a hill .
Check the transmission fluid level with the en-
gine running, the shift lever in Park, and the vehicle
LEVEL . DO NOT RACE ENGINE .
NOTE:
If the vehicle has recently been operated
for an extended period at high speed or in city
traffic in hot weather or the vehicle is being used
to pull a trailer, an accurate fluid level cannot be
determined until the fluid has cooled down -
usually about 30 minutes after the vehicle has
been parked .
Remove the dipstick and touch the transmission
end of the dipstick cautiously to find out if the fluid
is cool, warm, or hot.
Wipe the dipstick clean and re-insert until cap
seats. Remove dipstick and note reading.
* If the fluid feels cool, about room temperature,
65°F . (18 .3°C.) to 85°F . (29.4°C.), the level should be
1/8 to 3/8 inch below the "ADD" mark .
* If the fluid feels warm the level should be close
to the "ADD" mark (either above or below) .
* If the fluid feels hot (cannot be held comforta-
bly) the level should be between the "ADD" and
"FULL" marks.
NOTE :
DO NOT OVERFILL . It takes only one
pint to raise level from ADD TO FULL with a
hot transmission .
Draining Bottom Pan and Replacing Intake Pipe
and Filter Assembly
To drain bottom pan only, eliminate steps 5 and