
Water in Fuel 
Sometimes, water can be  pumped into your fuel  tank along with your diesel 
fuel. This  can  happen if a service  station doesn’t regularly inspect  and clean 
its fuel tanks,  or if it gets contaminated  fuel from  its suppliers. 
If this  happens,  a “WATER IN FUEL” light will come  on. If it  does,  the 
excess  water 
must be drained.  Your dealer  can do this  for you. 
This  light 
also should  come on briefly  when you start your engine, as a 
check. If it doesn’t, have  it fixed so it will be  there  to  let you  know if you 
ever  do  get  water 
in your fuel. 
If  the light  comes on at any  other  time,  use this chart. 
“WATER IN FUEL” LIGHT  CHART 
Problem 
Light  comes  on intermittently. 
Light stays on: 
1. At temperatures  above 
freezing. 
2. At temperatures  below 
freezing. 
Recommended  Action 
Drain  water from fuel filter. 
Drain  fuel  filter immediately. 
If no 
water  can be drained  and light stays 
on,  see  your dealer  for  assistance. 
Drain  fuel filter immediately.  If  no 
water  can be drained 
- water  may 
be  frozen.  Open 
the air bleed  valve 
to check for 
fuel pressure.  If  no fuel 
pressure 
is present, replace the fuel 
fi 1 ter. 
3. Immediately after  refueling - Fuel  tank purging required.  See 
large  amount 
of water possibly your dealer  for  assistance. 
pumped  into fuel tank. 
Hesitation  or “flat”  performance  at 
high speed or during  hard acceleration 
may  be  an  indication of premature fuel  filter plugging  due to dirty  or 
contaminated 
fuel. The  filter  element may need to be changed if this 
happens.  See your  dealer  for  assistance. 
If you  drive  when  this  warning  light is on,  you  can  damage  your 
fuel  injection  system  and  your  engine. 
If the  light  comes  on  right 
after  you  refuel, 
it means  water  was  pumped  into  your  fuel  tank. 
Turn 
off your  engine  immediately.  Then,  have  the  water  drained 
at  once. 
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3. Close the air bleed  valve. 
4. Turn  the ignition  key to “Start”  for 10 to 15 seconas  at  a time  until your 
engine  starts. 
Fuel Filter Replacement  (Diesel  Engines) 
If you  want  to change the  fuel filter  yourself,  here’s  how  to  do it: 
Drain  fuel  from  the filter  by opening  the  air bleed  valve  and  the water  drain 
valve.  This prevents  the 
fuel from  spilling  as you replace  the  filter.  Drain  the 
fuel  into a  fuel-resistant  container and dispose 
of it properly. 
1. Turn  off  the  engine and apply  the parking brake. 
2. Take  off the fuel tank cap. This  releases  vacuum in the  tank. 
3. The filter  is  located  at  the  rear of the  intake  manifold. 
4;: . 
4. Unscrew  and 
remove  the ring 
nut  from  the top 
of the filter head. 
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Engine  Oil  Additives 
Don’t  add anything to your  oil.  Your GM dealer is  ready  to advise  if  you 
think something should  be added. 
When  to  Change  Engine  Oil 
See  if  any  one of these  is true  for you: 
Most  trips are less  than 4 miles (6 km). 
0 It’s  below  freezing  outside  and  most  trips  are  less  than 10 miles (16 km). 
The engine  is  at low speed  most  of  the  time (as in door-to-door 
You tow  a  trailer often. 
delivery, 
or in  stop-and-go  traffic). 
Most  trips are through  dusty  places. 
The vehicle  is frequently  operated  off-road. 
If  any  one 
of these  is true for  your  vehicle,  then you need  to  change  your oil 
andfifilter every 3,000 miles (5 000 km) or 3 months - whichever  comes 
first 
. 
Light  Duty Emissions: 
If none of them  is true, change the  oil  every 7,500 miles (12 500 km) or 
12 months - whichever  comes first. Change  the filter  at  the first oil change 
and  at every other  oil change after  that. 
Heavy Duty  Emissions: 
If none of them is  true,  change  the  oil  every 6,000 miles ( 10 000 km) or 
12 months - whichever  comes first. Change  the filter  at  the  first oil  change 
and  at  every  other oil change after  that  if  mileage  determines  when  you 
change your oil. 
If time determines  when  you change your oil, change  the 
filter each time  you change  your 
oil. 
Engine  Coolant  Heater  (Engine  Block  Heater) 
An engine coolant heater can  be a  big  help if you have  to park  outside  in 
very  cold weather, 
0°F (-1 8 “C)  or  colder.  If  your vehicle  has  this option, 
see “Engine Coolant  Heater 
” in the Index. 
What  to Do with Used Oil 
Did  you  know that  used  engine oil contains  certain elements  that may be 
unhealthy  for your  skin and could even cause cancer? Don’t let  used oil stay 
on  your  skin for very  long.  Clean your  skin  and  nails  with  soap and  water, 
or 
a good  hand  cleaner.  Wash  or properly  throw  away  clothing or rags 
containing 
used engine oil. (See the manufacturer’s  warnings  about  the use 
and disposal of oil  products.) 
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Used  oil can be a real threat to the  environment. If you change your own oil, 
be sure to drain all  free-flowing oil from the filter before disposal.  Don't ever 
dispose  of oil  by putting  it  in  the  trash,  pouring  it on the  ground,  into  sewers, 
or  into  streams  or  bodies  of  water. Instead,  recycle  it  by taking  it  to  a place 
that  collects  used oil. If  you  have  a problem  properly  disposing  of your  used 
oil,  ask  your  dealer,  a service  station  or  a local  recycling  center  for help. 
Engine  Oil  (Diesel  Engines) 
It's  a good  idea to check  your engine  oil level every time  you  get fuel. In 
order to  get an accurate  reading, the oil  must  be  warm  and  the  vehicle must 
be on level ground. 
A 
Turn  off  the  engine 
and  give  the oil a few 
minutes to drain  back 
into the  oil  pan. If you 
don't,  the oil dipstick 
might  not  show  the 
actual  level. 
To Check Engine Oil 
Pull out the dipstick and clean  it with a paper  towel  or  a cloth,  then push  it 
back 
in all  the  way.  Remove  it  again, keeping the  tip lower. 
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This doughnut-shaped  logo (symbol) is used on most oil containers  to help 
you  select  the correct oil. 
You should look for this on the oil container,  and  use only those oils that 
display  the logo. 
GM Goodwrench@  oil (in  Canada, GM Engine Oil) meets  all the 
requirements  for  your vehicle. 
Engine  Oil  Additives 
Don’t add anything to your oil. Your GM dealer  is  ready to advise if you 
think  something  should be added. 
When to Change  Engine Oil 
See  if any one of these is true for you: 
Most  trips are less  than 4 miles (6 km). 
0 It’s below freezing  outside  and  most  trips are less than 10 miles 
0 The  engine  is at low  speed  most of the  time  (as in door-to-door 
(16 km). 
delivery, 
or in stop-and-go  traffic). 
You tow a trailer  often. 
0 Most trips are through dusty  places. 
The vehicle is frequently operated  off-road. 
If  any 
of these is true for your vehicle, then you  need  to  change your oil and 
filter 
every 2,500 miles (4 000 km)  or 3 months - whichever  comes  first. 
If none of them is true, change  the oil  and  filter every 5,000 miles 
(8 000 km) or 12  months - whichever comes first. 
What to Do with  Used  Oil 
Did  you know that used engine  oil contains  certain elements that may  be 
unhealthy  for your  skin and could  even cause  cancer?  Don’t let  used  oil  stay 
on  your 
skin for  very  long. Clean  your skin and nails with soap  and  water, 
or 
a good  hand cleaner.  Wash or properly  throw  away  clothing or rags 
containing  used engine 
oil. (See the manufacturer’s  warnings about the use 
and  disposal 
of oil products.) 
Used  oil can  be a real threat to the environment. 
If you  change  your  own  oil. 
be  sure to drain  all  free-flowing  oil  from the filter before disposal.  Don’t 
ever  dispose  of oil  by putting 
it in the  trash,  pouring it on the ground,  into 
sewers,  or into streams 
or bodies  of water.  Instead, recycle it by taking it to 
a place  that collects  used oil. If  you  have a problem  properly  disposing  of 
your  used  oil, 
ask your dealer, a service station or a local recycling  center 
for  help. 
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To remove the air 
cleaner filter 
on a  gas 
engine  or 
a 6.5 liter 
naturally  aspirated 
diesel,  turn  the wing 
nuts 
to the  left. 
Remove  the  cover  and 
change  the  filter. 
To remove  the air cleaner  filter on  a 6.5 liter  turbocharged  diesel,  first 
remove  the rubber  elbow.  Remember  to observe  the  caution  about 
turbocharger  blades  on  the  rubber  elbow, 
Then, unhook  the 
cover  retaining  clips 
and  push  the  rear 
of 
the cover  toward  the 
engine. 
Automatic Transmission Fluid 
When to Check  and  Change 
A good  time to check  your  automatic  transmission  fluid level is  when  the 
engine 
oil is changed. Refer to the Maintenance Schedule to determine 
when  to change  your fluid. 
See “Scheduled  Maintenance  Services” in  the 
Index. 
How to Check 
Because  this  operation  can  be a  little  difficult, you may  choose to have  this 
done  at  a 
GM dealership Service  Department. 
If you do it yourself,  be sure to follow all the instructions  here,  or you  could 
get 
a false reading on the  dipstick. 
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WOW to Add Fluid 
Refer to the Maintenance Schedule to determine  what kind of transmission 
fluid to  use. See “Recommended Fluids and  Lubricants’’  in  the Index. 
If  the fluid level 
is low,  add only enough  of the proper fluid to bring  the 
level  up  to the 
COLD area for a cold check or  the HOT area for a hot  check. 
It  doesn’t take  much fluid, generally 
less than a pint. Don’t  overfill. We 
recommend  you  use 
only fluid labeled  DEXRON@-I11  or DEXRON@-IIE, 
because fluids  with that label are made especially  for your automatic 
transmission. Damage caused 
by fluid other than  DEXRON@-I11  or 
DEXRON@-IIE is not covered 
by your  new vehicle warranty. 
After adding fluid, recheck the fluid level as described under “How to 
Check.” 
When  the correct fluid level  is obtained,  push the dipstick back  in all 
the  way; then  flip the handle down  to lock the dipstick 
in place. 
Manual  Transmission  Fluid 
When to Check 
A good time to have it checked is when  the engine oil is changed. However, 
the fluid 
in your manual transmission doesn’t require changing. 
How to Check 
Because this operation  can be a little  difficult,  you  may choose to have  this 
done  at a 
GM dealership Service Department. 
If you  do it yourself,  be sure  to follow all the instructions here, or you  could 
get 
a false reading. 
NOTICE: 
Too much  or  too  little  fluid  can  damage  your  transmission. Too 
much  can  mean  that  some of the  fluid  could  come  out  and  fall  on 
hot  engine  parts  or exhaust  system,  starting  a  fire.  Be  sure  to get 
an  accurate  reading  if 
you check  your  transmission fluid. 
Check the fluid level only  when  your engine  is off, the vehicle is parked  on 
a level place and the transmission  is cool enough for you  to rest your fingers 
on  the transmission case. 
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Specification Charts 
Replacement  Parts 
Replacement part numbers listed in this  section are based on the latest 
information available 
at the  time of printing,  and are subject to change.  If a 
part listed  in this  manual 
is not the same as the part used in your vehicle 
when 
it was built,  or if  you  have any questions,  please  contact your GM 
truck  dealer. 
Engine  Identification -Gas Engines 
Engine 
Type  VIN  Code 
Fuel System 
Produced  By 
Emissions 
5.7L 
V8 
K 
TBIT 
U.S., CAN. 
JJD*/HD** 
“Light  Duty Emissions  with 
8500 GVWR and  below or: 
**Heavy  Duty  Emissions with  8501 GVWR and above 
?Throttle  Body  Injection 
Engine  Identification  -Diesel  Engines 
Engine 
Type  VIN  Code 
Fuel  System 
Produced  By 
Emissions 
Wheel Nut Torque 
MODEL 
C 1500 
K 1500, C-K 2500 
C-K 2500 
6.5L 
V8 
S 
Turbo  Diesel 
U.S. 
LD 
DESCRIPTION 
5 bolts (14mm) 
6 bolts (14mm) 
8 bolts (14mm) 
6.5L 
V8 
F 
Turbo  Diesel 
U.S. 
HD 
TORQUE 
120 ft. lbs. (1 60 Nom) 
120 ft. lbs. ( 1 60 Nom) 
I20 ft. Ibs. (I 60 Nom) 
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