Waterproof Grease - Symbol "S4; Hydraulic Brake Fluid - Symbol "S12; Clutch And Brake Master Cylinder; Soft, Smooth Cup Grease - Symbol "S16 - GMC 4000 Series Service Manual

This type of lubricant should be waterproof
grease containing 20% to 35% calcium soap. On
models equipped with propeller shaft center bear­
ings, both sides of the shield should be packed
The fluid indicated by the symbol "S12" must
be genuine heavy duty brake fluid meeting the
heavy duty standards of S.A.E. 70R3.
CLUTCH AND BRAKE
MASTER CYLINDER
Check master cylinder fluid level at intervals
indicated on charts. Remove dirt from around the
plug or cover, then remove.
Fill with fluid until level is within 1 /2 " of open­
ing. Inspect to be sure vent hole is clean, then in­
stall and tighten filler plug or cover (refer to
figure 15).
Lubricant indicated by the symbol "S16" on
charts should be No. 2 V Z soft, smooth cup grease.
Fibrous types of lubricant are not recommended
for spherangular (barrel) type roller bearings.
High quality lithium soap grease is also highly
recommended, especially where corrosion is evi­
dent due to moisture.
A sem i-fluid grease having extreme pressure
properties and containing zinc oxide.
At regular lubrication intervals, or whenever
accessible during repairs or overhaul, apply lub­
ricant sparingly to the following items and areas:
Door Striker Plates
Door Checks and Trunnions
Door Hinge Pins
Door Lock Remote Control Link
Cowl Ventilator Linkage
G M C S E R V I C E M A N U A L
WATERPROOF GREASE
(SYMBOL "S4" O N CHARTS)
with this lubricant at the time of assembly. This
lubricant excludes water and dirt from bearing.
Refer to "PROPELLER SHAFTS" (SEC. 4D) of this
manual for procedure.
HYDRAULIC BRAKE FLUID
(SYMBOL "SI 2 " ON CHARTS)
Figure I S — Clutch and Brake Master Cylinder (Typical)
SOFT, SMOOTH CUP GREASE
(SYMBOL "SI 6 " O N CHARTS)
tion Charts, or whenever wheel hub is removed,
bearings should be cleaned, inspected, and re­
lubricated as previously described under "Symbol
S2."
SPECIAL GREASE
(SYMBOL "SI 7 " O N CHARTS)
lubricated periodically, many other units use this
lubricant at time of assembly after overhaul, as
indicated in various sections of this manual.
REAR WHEEL BEARINGS
At regular intervals as specified on Lubrica­
Seat Adjuster Slides
Door Lock Mechanism
Door Dove Tails
Window Regulator Channels
Window Regulators
Hood Hinges
Tilt Cab Guide Pin
In addition to item s just mentioned, which are
Sec. 0
Page 15
LUBRICATION