
Listed are four situations you may experience with your  f~~el gage: 
At the gas station. the fuel pump shuts  off before  the gage reads  full. 
It lakes a little more or less  fuel  to fill up  than  the  fuel gage indicated. 
For  example,  the gage  may have  indicated  the  tank  was  half 
full, but it 
actually took a little more  or less  than  half  the tank's  capacity to fill the 
, tank. 
The  gage  moves a little when  you turn a corner or speed  up. 
The  gage  doesn't go back  to  empty when  you turn off the ignition. 
None  of these indicate 
a problem with the  fuel  gage. 
For information on how to fill your fuel tank,  see "Fuel - Filling  Your 
Tank" 
in the Index. 
For your  fuel tank  capacity,  see "Fuel  -Tank  Capacity" in the Index. 
Engine  Coolant  Temperature  Gage 
This  gage  shows  the engine  coolant  temperature. Most of  the time. the gage 
pointer 
will show your coolant  temperature  at 2 10°F (99"C), or  less. But, if 
you  are pulling a heavy  load or driving LIP hills, your coolant temperature 
may  rise and 
fall near  the  red  260°F ( 128°C) mark. This is normal. If the 
gage  pointer  moves to the  red  260°F 
(128°C) mark, your engine  is too hot! 
It means that your engine coolant  has overheated. You should pull off the 
road, 
stop your vehicle.  and  turn off the engine as soon as possible. 
Hot Coolant Can Burn  You  Badly! 
In "Problems  on  the Road," this manual  shows what to do. See "Engine 
Overheating" 
in thc Index. 
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Loading Your Vehicle 
- 
DSI/KPA (COL3) 
The Certification/Tire  label is found on the rear  edge of the  driver’s  door or 
in the Incomplete  Vehicle Document  in the cab. 
The  label  shows  the size  of your  original tires and the inflation pressures 
needed  to obtain 
the gross  weight  capacity of your vehicle.  This is called the 
GVWR  (Gross  Vehicle Weight Rating).  The 
GVWR includes  the  weight of 
the vehicle,  all  occupants,  fuel  and  cargo. 
The  CertificatiodTire  label also  tells  you the maximum  weights for  the 
front and  rear  axles,  called  Gross  Axle Weight Rating (GAWR). 
To find out 
the actual  loads 
on your front  and rear  axles,  you need  to go  to  a weigh 
station and weigh your vehicle.  Your dealer  can  help 
you with this. Be sure 
to spread  out your load  equally on both  sides  of the centerline. 
Never  exceed  the GVWR  for your  vehicle,  or the  GAWR  for either  the front 
or  rear  axle. 
And, 
if you  do have  a  heavy load, you should  spread it out. 
A CAUTION-: 
In  the  case of a sudden  stop or  collision,  things  carried  in the  bed 
of  your  truck  could  shift  forward  and  come  into  the  passenger \
 area,  injuring  you  and 
others. If you  put  things  in  the bed of 
your  truck,  you 
should make  sure  they  are  properly  secured. 
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You can ask your dealer for  our trailering  information  or  advice,  or you can 
write us  at the address listed 
in your  Warranty  and Owner  Assistance 
Information  Booklet. 
In  Canada,  write to: 
General  Motors 
of Canada Limited 
Customer  Assistance  Center 
1908 Colonel  Sam Drive 
Oshawa,  Ontario 
Ll H 8P7 
Weight of the  Trailer  Tongue 
The  tongue  load (A) of any trailer  is  an important weight  to measure 
because 
it affects the total  or gross  weight of your vehicle. The  gross vehicle 
weight  (GVW)  includes 
the curb weight of the vehicle,  any cargo you may 
carry 
in it, and the people who will  be  riding in the vehicle.  And if  you  will 
tow  a trailer,  you must add the tongue load to 
the GVW because your 
vehicle  will  be carrying that weight, too.  See “Loading  Your Vehicle” 
in the 
Index 
for more information about  your vehicle’s maximum load capacity. 
A B 
If you’re  using a “dead-weight”  hitch, the trailer  tongue (A) should weigh 
10% of the total loaded trailer weight (B). If you have  a 
“weight-distributing”  hitch, 
the trailer tongue (A) should weigh 12% of the 
total  loaded  trailer weight 
(B). 
After you’ve  loaded your trailer,  weigh the trailer and  then the tongue, 
separately, 
to see  if the weights are  proper. If they  aren’t, you may be able to 
get  them  right  simply by moving  some items around in the trailer. 
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What to Use 
Refer to the  Maintenance  Schedule  to determine  what kind of lubricant  to 
use.  See “Recommended  Fluids  and Lubricants” 
in the  Index. 
C3 (3500 H.D.) Trucks  Equipped  with  Dana  Rear Axle 
Additional rear  axle scheduled  maintenance  is required on 3500 H.D. 
models  equipped  with Dana  rear axles when they are driven under the 
following  conditions: 
0 Extreme  loading (at or near  GVWR)  or trailer  towing,  and: 
Operation  above 45  mph for extended  periods  of time 
Vehicles  used 
in any  of  these conditions  require the rear axle lubricant (SAE 
8OW-90 - GL-5) be changed  every 3 months or 3,000 miles, whichever 
comes  first. 
To reduce  required  maintenance, SAE 75W-140 synthetic gear lubricant 
may  be  used. With  the  use  of synthetic 
SAE 75W-140  lubricant, the fluid 
change intervals  may be  increased  to  30,000 miles. Before  using SAE 
75W-140, it is important  to drain and flush the axle  with clean mineral 
based  (non-synthetic)  axle lubricant.  Fluid capacity  is 4.12  qts.  (3.9L). 
Four-  Wheel  Drive 
Most  lubricant  checks in this section also apply to  four-wheel-drive 
vehicles.  However,  they have two additional  systems that  need lubrication. 
Transfer  Case 
When  to  Check  Lubricant 
Refer  to the Maintenance  Schedule  to determine  how often  to  check the 
lubricant.  See  “Periodic  Maintenance  Inspections” 
in the Index. 
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Wheel  Alignment  and  Tire  Balance 
The wheels on your vehicle  were aligned  and balanced  carefully  at the 
factory 
to give  you the longest tire life and best overall  performance. 
In most cases, you will not need to have your wheels aligned  again. 
However,  if 
you notice unusual  tire wear  or your  vehicle  pulling  one  way or 
the other, 
the alignment  may need to be reset. If you  notice  your  vehicle 
vibrating  when driving 
on a smooth  road, your wheels  may  need to be 
rebalanced. 
Wheel  Replacement 
Replace  any wheel that  is bent,  cracked,  or badly rusted  or corroded. If 
wheel nuts  keep  coming  loose,  the wheel,  wheel bolts, and  wheel nuts 
should be  replaced. 
If the wheel  leaks air,  replace it (except  some aluminum 
wheels, which  can  sometimes  be repaired).  See your 
GM dealer  if any of 
these  conditions  exist. 
Your dealer  will know the kind  of wheel  you need. 
Each  new wheel  should have the same load  carrying capacity, diameter, 
width, offset,  and be mounted the  same way as the  one 
it replaces. 
If you need to replace  any of your  wheels, wheel bolts,  or wheel  nuts, 
replace them  only with new 
GM original  equipment  parts. This way,  you 
will be sure to have  the right  wheel, wheel bolts,  and wheel nuts for your 
vehicle. 
A CAUTION: 
Using  the wrong replacement  wheels,  wheel  bolts,  or wheel  nuts 
on  your  vehicle  can be dangerous.  It could  affect  the  braking 
and  handling 
of your  vehicle,  make your tires  lose air  and  make 
you  lose  control, You could have a  collision in which 
you or 
others  could be injured.  Always  use  the correct  wheel,  wheel 
bolts,  and wheel 
nuts for replacement. 
NOTICE: 
The  wrong  wheel  can also cause problems  with bearing  life, 
brake  cooling,  speedometer/odometer calibration, headlamp 
aim,  bumper  height,  vehicle  ground clearance,  and  tire or  tire 
chain clearance to  the body  and chassis. 
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