Chevrolet 1977 light duty truck, Service Manual

Page: 12 / 861

• If it feels hot (cannot be held comfortably), the
level should be between the
A D D
and
FU L L
marks.
Drain Intervals
The transmission o p e ra tin g tem perature resulting
from the type o f driving conditions under which your
vehicle is used is the m ain consideration in establishing
the p ro p er frequency of transm ission fluid changes.
C h an g e the transm ission fluid and filter every
15,000 miles (12,000 miles Heavy Duty Emission
Vehicles), if the vehicle is usually driven u nder one or
more of the following conditions which are considered
severe transmission service:
• In heavy city traffic.
• W here the outside tem p eratu re regularly reaches
90 °F.
• In very hilly or m ountainous areas.
• Freq u en t trailer pulling.
• C o m m ercial uses, such as taxi, police car or
delivery service.
If you do not use your vehicle und er any o f these
conditions, change the fluid and filter every 60,000 miles,
(24,000 miles Heavy Duty Emission Vehicles).
T o C h a n g e T u rb o H y d ra -M a tic 4 0 0 an d T urbo
H y d r a -M a tic 3 5 0 flu id ,
remove fluid from the transm is­
sion sump, add approxim ately 7.5 pints U.S. m easure
(6.25 pin ts Im perial m easure) for the T u rb o H ydra-M atic
400 and 2-1/2 qts. U.S. m easure (2 qts. Imperial
m easure) for the T u rb o H ydra-M atic 350 o f fresh fluid,
to return level to pro p er m ark on the dipstick.
E very 6 0 ,0 0 0 M ile s ( 2 4 ,0 0 0 m iles H e av y Duty
E m ission V e h ic le s ) -
the T u rb o H ydra-M atic 400 tran s­
mission sum p filter should be replaced.
3-A N D 4-SPEED M A N U A L T R A N M IS S IO N
Lubricant
Every 12 m onths or 7,500 miles (4 m onths or 6.000
miles Heavy Duty Emission Vehicles), whichever occurs
first, check
lubricant level and add lubricant, if
necessary, to fill to level o f filler plug hole with SAE 80W
or SAE 80W-90 GL-5 G e a r Lubricant. If tem peratures
below + 3 2 ' F are expected, use SAE 80W GL-5 G e a r
L u b rican t only. F or those vehicles normally operated in
C a n a d a , use SAE 80W GL-5 G e a r L ubricant only.
T R A N S M IS S IO N S H IF T LIN K A G E
(M A N U A L A N D A U T O M A T IC )
Every 7,500 miles or 12 m onths (6,000 miles or 4
m onths Heavy Duty Emission Vehicles), lubricate shift
linkage and, on M an u al transm ission floor control, lever
contacting faces with w ater resistant EP chassis lubricant
which meets G e n eral M otors Specification G M 6031-M .
C lutch
The clutch pedal free travel should be checked at
regular intervals.
Lubricate the clutch cross-shaft at fitting (on Series
10 Forw ard Control models also lubricate the clutch
linkage idler lever at fitting) every 7,500 miles or 12
m onths (6,000 miles or 4 m onths Heavy D uty Emission
Vehicles) with water resistant EP chassis lubricant which
meets G e n e ra l Motors Specification G M 6 0 3 l-M.
REAR AXLES
S tan d ard
Every 12 m onths or 7,500 miles (4 m onths or 6,000
miles Heavy Duty Emission Vehicles), whichever occurs
first, check lubricant level and add lubricant, if
necessary, to fill to level o f filler plug hole. Use SAE 80W
or SAE 80W-90 GL-5 G e a r Lubricant. For those vehicles
normally operated in C anada, use SAE 80W GL-5 G ear
Lubricant.
Positive Locking or Positraction
Every 12 months or 7,500 miles (4 m onths or 6,000
miles Heavy Duty Emission Vehicles), whichever occurs
first, check lubricant level and add SAE 80W or SAE
80W-90 GL5 gear lubricant, if necessary, to fill to level
of filler plug hole.
PROPELLER SH A FT SLIP J O IN T S
Propeller shaft slip joints should be lubricated every 7,500
miles or 12 months (6,000 miles or 4 months Heavy Duty Emis­
sion Vehicles) with water resistant EP chassis lubricant which
meets General Motors Specification GM 603l-M.
U N IV E R S A L JO IN T S
All universal joints are the needle bearing type.
Lubricate those universal joints (depending on truck
model) equipped with lube fittings every 7,500 miles or
12 months (6,000 miles or 4 m onths Heavy Duty
Emission Vehicles) with water resistant EP chassis
lubricant which meets G e n eral M otors Specification G M
6 0 3 l-M. More frequent lubes may be required on heavy
duty or "O ff the R o a d " operations.
WHEEL BEARING S
F ro n t
NO TE: Use wheel bearing lubricant G M Part No.
1051344 or equivalent which meets all req u ire­
ments o f G eneral Motors Specification G M 6031 -
M.
Due to the weight o f the tire and wheel assembly it
is recom m ended that they be removed from hub before
lubricating bearings to prevent d a m a g e to oil seal. Then
remove the front wheel hub to lubricate the bearings.
The bearings should be thoroughly cleaned before
repacking with lubricant.
Front wheels are equipped with tapered roller