
New Vehicle “Break-In” - 3500 HD Model 
If you have a 3500 HD model, your parking brake requires a special 
break-in  procedure.  See “Parking  Brake” 
in the Index. 
Ignition Switch 
Use  your  key to start your  vehicle.  The key lets you turn the ignition switch 
to  five  different positions: 
2 
5 
1. OFF 
2. RUN 
3. START 
4. ACC 
5. LOCK 
ACC  (Accessory): 
ACC lets you use things like the radio, power  windows 
and the windshield  wipers when the engine is off. To get into ACC, push in 
the key and turn it toward you.  Your steering  wheel  will  remain locked,  just 
as it was before you inserted  the key. 
LOCK: This  position  locks your ignition,  steering wheel and  transmission. 
It’s 
a theft deterrent  feature. You will only  be able  to remove  your key  when 
the ignition 
is turned  to LOCK. 
OFF: This position  lets  you turn  off the  engine  but still  turn the steering 
wheel.  It  doesn’t lock the  steering wheel like  LOCK. Use 
OFF if  you must 
have  your  vehicle 
in motion while the  engine is off (for example, if your 
vehicle  is  being pushed). 
RUN: This is the position  for  driving. 
START:  This  starts  your engine. 
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Remember: Anti-lock doesn’t  change  the time  you need  to get your  foot up 
to  the  brake pedal.  If  you get  too  close  to  the vehicle in front  of you,  you 
won’t  have  time 
to apply your brakes if that vehicle  suddenly  slows  or 
stops.  Always  leave  enough  room up ahead to stop, even though 
you have 
anti-lock  brakes. 
To Use Anti-Lock 
Don’t pump the brakes. Just hold the brake pedal down and  let  anti-lock 
work  for you.  You  may  feel the brakes  vibrate,  or you  may notice some 
noise,  but this  is normal. On vehicles 
with four-wheel  drive, your anti-lock 
brakes work  at  all times 
- whether  you are in two-wheel  drive or 
four-wheel  drive. 
Braking  in  Emergencies 
Use your  anti-lock  braking system  when  you  need to. With anti-lock,  you 
can  steer  and brake  at the  same  time.  In many  emergencies,  steering can 
help  you more  than even the  very best braking. 
Steering 
Power  Steering 
If  you  lose  power  steering assist  because the engine  stops  or  the  system is 
not  functioning,  you can steer  but it  will  take much  more  effort. 
Steering  Tips 
Driving on Curves 
It’s important to take  curves  at a reasonable  speed. 
A lot of the “driver  lost  control’’ accidents  mentioned  on the  news happen 
on  curves.  Here’s  why: 
Experienced  driver  or beginner,  each of 
us is subject to the  same  laws of 
physics  when  driving on curves.  The  traction of the  tires  against  the road 
surface  makes 
it possible  for the  vehicle  to change  its path  when you turn 
the  front  wheels. 
If there’s no traction,  inertia will keep  the vehicle  going  in 
the  same  direction.  If you’ve  ever  tried to steer 
a vehicle  on wet  ice, you’ll 
understand  this. 
The  traction 
you can get in a curve  depends on the condition  of your tires 
and the road  surface, the angle  at  which the  curve is banked,  and your 
speed.  While  you’re 
in a  curve, speed is the one  factor you can  control. 
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Here  are  some  other things to consider as you approach  a hill. 
Is  there a constant incline,  or  does  the hill get sharply steeper  in places? 
Is there  good traction on the hillside,  or will  the  surface cause tire 
slipping? 
Is there a straight path  up or down the hill so you won’t have to make 
0 Are there obstructions on the  hill that can  block your path (boulders, 
turning maneuvers? 
trees, 
logs or  ruts)? 
What’s  beyond  the  hill? Is there a cliff, an  embankment, a drop-off,  a 
fence?  Get  out and walk 
the hill if you  don’t know.  It’s the smart  way 
to find out. 
Is the hill simply too  rough?  Steep  hills often have ruts, gullies, troughs 
and  exposed  rocks because they are more  susceptible 
to the effects of 
erosion. 
Driving Uphi// 
Once you decide  you can safely  drive up the hill,  you  need  to take some 
special  steps. 
0 Use  a low gear and get  a firm  grip on the  steering  wheel. 
0 Get  a smooth start  up the hill and  try to maintain your speed.  Don’t use 
more  power  than  you need, because  you don’t want your wheels 
to start 
spinning  or  sliding. 
Try to  drive  straight up the hill  if  at  all  possible. If the path twists and 
turns,  you might want to find  another route. 
1 A CAUTION: 
nrning or driving  across  steep  hills  can  be  dangerous.  You 
could  lose  traction,  slide  sideways,  and  possibly 
roll over. You 
could  be  seriously  injured  or  killed.  When  driving  up hills, 
always  try  to 
go straight up. 
Ease  up on your speed  as you  approach the top of the hill. 
0 Attach  a  flag to the vehicle to make  you more visible to approaching 
traffic  on trails 
or hills. 
Sound the horn as you  approach the top of the hill to let opposing 
traffic 
know you’re  there. 
to  oncoming  traffic. 
Use your headlights even  during the day. They make  you more visible 
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NOTICE: 
Your surge  tank  pressure  cap  is a unique 15 psi (105 kPa) 
pressure-type  cap  for  use  with  surge  tank  cooling  systems  only. 
It must  be  tightly  installed  to  prevent  coolant loss and  possible 
engine  damage  from  overheating.  Be sure  the  arrows  on  the  cap 
line  up with  the  top  tube  of the  coolant  surge  tank. 
Thermostat 
Engine  coolant  temperature  is  controlled  by a  thermostat  in  the  engine 
coolant  system.  The  thermostat  stops  the  flow 
of coolant  through  the 
radiator  until  the  coolant  reaches  a  preset  temperature. 
When  you replace  your  thermostat,  an  AC@ thermostat  is  recommended. 
Power  Steering  Fluid 
How To Check Power  Steering  Fluid 
When  the  engine  compartment  is  cool,  unscrew  the  cap  and  wipe \
 the 
dipstick  with a  clean  rag.  Replace  the  cap  and  completely  tighten  it. Then 
remove  the  cap  again  and  look  at  the  fluid  level  on  the  dips\
tick. 
The  level  should  be at the 
FULL COLD  mark. Add  enough  fluid  to  bring 
the  level 
up to  the  mark. 
A fluid loss in this  system  could  indicate  a  problem.  Have  the  system 
inspected  and  repaired. 
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What to Add 
Refer to the Maintenance  Schedule to determine what  kind of' tluid to use 
See  "Recommended  Fluids  and Lubricants" 
in the Index. 
NOTICE: 
When  adding  power  steering  fluid  or  making  a  complete  fluid 
change,  always  use  the  proper  fluid.  Failure  to  use 
the proper 
fluid  can  cause  leaks  and  damage  hoses  and  seals. 
Hydro-Boost  Brake  System  (Hydraulic Pump) 
The power  steering pump is also  used as the Hydro-boost pump. Refer to 
"Power  Steering  System'' 
in this  section  when checking fluid level or 
adding  fluid. 
Windshield  Washer  Fluid 
What to Use 
When you need  windshield  washer  fluid, be sure to read  the manuhcturer's 
instructions  before  use. 
If you will be operating  your  vehicle in an area 
where the temperature 
may fall below  freezing, use a fluid that has 
sufficient protection  against  freezing. 
To Add 
Open the cap labeled 
WASHER FLUID 
ONLY.  Add  washer 
fluid 
until the  tank  is 
full. 
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Part C: Periodic  Maintenance  lnspections 
Listed below are inspections and  services which should  be performed  at 
least twice  a year  (for instance, each  spring and 
fall). You should  let your 
GM  dealer’s  service  department  or  other  qualified  service center  do these 
jobs.  Make  sure any necessary repairs  are completed  at once. 
Steering  and Suspension  Inspection 
Inspect the front and rear  suspension  and steering  system for damaged. 
loose  or  missing parts, signs  of wear, 
or lack  of  lubrication.  Inspect power 
steering lines and hoses  for proper hookup, binding,  leaks,  cracks,  chafing, 
etc.  (On  vehicles equipped  with manual steering gear, check  for  seal 
leakage.) 
Exhaust  System  Inspection 
Inspect the  complete  exhaust  system.  Inspect the  body  near the exhaust 
system. 
Look for broken.  damaged,  missing or  out-of-position  parts as well 
as  open  seams,  holes,  loose  connections, 
or other  conditions  which could 
cause  a heat  build-up 
in the floor  pan or could  let exhaust  fumes into the 
vehicle.  See  “Engine  Exhaust” 
in the Index. 
Accelerator  Control  System 
On gasoline  engines.  lubricate the pivot at the TBI throttle  lever stud  with 
engine 
oil. Do not oil any  accelerator  or  cruise control cables. Replace  any 
cables  that have  high effort  or  excessive  wear. 
Drive  Axle  Service 
Check readfront  axle  fluid level and  add as needed. Check constant  velocity 
Joints  and axle  seals  for  leaking. 
Transfer  Case  (Four-  Wheel  Drive)  Inspection 
Every 12 months or at  oil  change  intervals, check  front  axle and transfer 
case  and add  lubricant  when necessary.  Oil the control  lever pivot point and 
all exposed  control  linkage. Check  vent hose at transfer  case for kinks and 
proper  installation.  More  frequent  lubrication may  be required  on  off-road 
use. 
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USAGE 
Power  Steering  System Manual Transmission  (5-Speed 
with Low Gear,  RPO MT8) 
Manual Transmission  (5-Speed 
without  Low Gear, RPO  MG5) 
Automatic Transmission  Key  Lock  Cylinders 
FLUIDLUBRICANT 
GM  Power  Steering Fluid (GM Part 
No. 10500 I7 or  equivalent). 
Castrol  Syntorq' 
LT or equivalent 
(GM  Part No.  12346191 
- 1 gal.) 
(GM  Part 
No. I23461  90 - 1 qt.). 
Synchromesh  Transmission Fluid 
(GM  Part 
No. 12345349 or  equiva- 
lent). 
DEXR0N'-I11  Automauc 
Transmission  Fluid. 
Lubricate 
with Multi-Purpose Lu- 
bricant  (GM Part No. I2345  120) or 
synthetic SAE SW-30  engine  oil. 
Automatic  Transmission  Shift 
Linkage 
Clutch  Fork  Ball Stud  (5-Speed 
with  Low  Gear) 
Floor  Shift  Linkage 
Chassis  Lubrication 
Front Wheel  Bearings 
Differential,  Standard,  Front and 
Rear Axle 
Differential, Locking 
Transfer  Case  Engine 
oil. 
Chassis  lubricant  (GM Part 
No. 
12346003 or equivalent)  or lubri- 
cant meeting requirements  of  NLGI 
Grade  2, Category  LB or GC-LB. 
Engine 
oil. 
Chassis  lubricant  (GM Part No. 
I2346003  or  equivalent)  or  lubri- 
cant meeting  requirements  of NLGI 
Grade 
2, Category  LB or GC-LB. 
Wheel bearing lubricant  meeting 
requirements 
of NLGI  Grade 2, 
Category  GC  or GC-LB  (GM Part 
No. I2346003  or  equivalent). 
Axle Lubricant  (GM Part No. 
105227 
1 ) or SAE 8OW-90  GL-5 
Gear  Lubricant. 
Axle Lubricant  (GM Part 
No. 
105227 1) or  SAE  80W-90  GL-5 
Gear  Lubricant. 
DEXR0N"-111  Automatic 
Transmission  Fluid. 
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Oil DieselEngines 
............................................... 6-21 
Additives 
................................................. 6-25 
Pressure  Gage  (See  “Gages” 
j 
ToCheck ................................................. 6-22 
WhatKindtoUse 
.......................................... 6-23 
WhentoAdd 
.............................................. 6-22 
WhentoChange 
............................................ 6-25 
What  to  Do  with  Used  Oil 
.................................... 6-25 
Gasoline  Engines 
............................................. 6-16 
Additives 
................................................. 6-20 
Pressure  Gage  (See  “Gages”) 
ToCheck 
................................................. 6-16 
WhatKindtoUse 
.......................................... 6-17 
WhentoAdd .............................................. 6-17 
When to Change ............................................ 6-20 
What  to  Do  with Used 
Oil .................................... 6-21 
Owner  Checks  and Services 
........................................ 7-93 
Parking  Brake  (See “Brakes-Parking”) 
On  Hills  (See “Towing-Parking  on  Hills’*j 
Over  Things  That  Burn 
........................................ 
Passing (See  “Drivin~-Passing”) 
Periodic Maintenance  Inspections  (See “Scheduled  Maintenance  Services”) 
Power 
Door  Locks  (See “Dood’j  2-31 
Steering 
...................................................... 4-7 
Steering  Fluid 
................................................ 640 
Take-Off 
.................................................... 4-35 
Winches 
..................................................... 4-34 
Radiator  Pressure  Cap 
............................................ 6-39 
Radio  (See “Audio  Systems”) 
Rear Axle  (See  ”Axle”) 
Recommended  Fluids and Lubricants  (See “Scheduled  Maintenance  Services“) 
Recovery  Hooks 
................................................. 5-40 
Replacement  Parts ............................................... 6-80 
Reporting  Safety  Defects  To The  United  States Government  (See “Safety  Defects”) 
Roadside  Assistance 
............................................... 8-5 
Rocking  Your  Vehicle ............................................ 5-39 
Rear Window  Defogger 
............................................ 3-4 
Safety  Belts ..................................................... 1-9 
Adults ...................................................... 1-12 
Center  Passenger  Position ....................................... 1-25 
Checking  Restraint  System ...................................... 1-44 
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