2007 CHEVROLET COLORADO transmission

Maintenance When Trailer Towing
Your vehicle will need service more often
when you’re pulling a trailer. SeeScheduled
Maintenance on page 442for more on this.
Things that are especially important in trailer
operation are automatic transmission uid
(don’t overll), engine oil, axle lubricant, belt,
cooling system and brake system. Each of these
is covered in this manual, and the Index will
help you nd them quickly. If you’re trailering,
it’s a good idea to review these sections before
you start your trip.
Check periodically to see that all hitch nuts
and bolts are tight.
Trailer Wiring Harness
Your vehicle may be equipped with a four-pin
trailer towing harness. This harness has a four-pin
trailer connector that is attached to a bracket on
the hitch platform. The four-wire harness contains
the following trailer circuits:
Yellow: Left Stop/Turn Signal
Green: Right Stop/Turn Signal
Brown: Taillamps/Park lamps
White: Ground
Trailer Recommendations
You must subtract your hitch load from the CWR
for your vehicle. Weigh your vehicle with your trailer
attached, so that you won’t go over the GVWR or
the GAWR.
You’ll get the best performance if you spread
out the weight of your load the right way, and if
you choose the correct hitch and trailer brakes.
For more information, seeTowing a Trailer
on page 306later in this section.
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Service........................................................ 324
Accessories and Modications................... 324
California Proposition 65 Warning.............. 324
Doing Your Own Service Work.................. 325
Adding Equipment to the
Outside of Your Vehicle......................... 325
Fuel............................................................. 326
Gasoline Octane........................................ 326
Gasoline Specications.............................. 326
California Fuel........................................... 326
Additives................................................... 326
Fuels in Foreign Countries........................ 327
Filling the Tank......................................... 328
Filling a Portable Fuel Container............... 330
Checking Things Under the Hood.............. 331
Hood Release........................................... 331
Engine Compartment Overview.................. 332
Engine Oil................................................. 333
Engine Oil Life System.............................. 336Engine Air Cleaner/Filter............................ 338
Automatic Transmission Fluid.................... 339
Manual Transmission Fluid........................ 342
Hydraulic Clutch........................................ 344
Engine Coolant.......................................... 345
Radiator Pressure Cap.............................. 348
Engine Overheating................................... 348
Cooling System......................................... 350
Engine Fan Noise..................................... 355
Power Steering Fluid................................. 355
Windshield Washer Fluid........................... 356
Brakes...................................................... 357
Battery...................................................... 361
Jump Starting............................................ 362
Rear Axle.................................................... 368
Four-Wheel Drive........................................ 368
Front Axle................................................... 369
Section 5 Service and Appearance Care
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A. Windshield Washer Fluid. See “Adding Washer
Fluid” underWindshield Washer Fluid on
page 356.
B. Engine Coolant Recovery Tank. SeeEngine
Coolant on page 345.
C. Engine Air Cleaner/Filter. SeeEngine
Air Cleaner/Filter on page 338.
D. Power Steering Fluid Reservoir (low in engine
compartment). SeePower Steering Fluid
on page 355.
E. Automatic Transmission Fluid Dipstick
(If Equipped). See “Checking the Fluid Level”
underAutomatic Transmission Fluid on
page 339.
F. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 333.
G. Radiator Pressure Cap. SeeCooling System
on page 350.
H. Remote Negative (−) Terminal (GND).
SeeJump Starting on page 362.
I. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 333.
J. Remote Positive (+) Terminal. SeeJump
Starting on page 362.K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 357.
L. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 433.
M. Battery. SeeBattery on page 361.
N. Hydraulic Clutch Fluid Reservoir (If Equipped).
SeeHydraulic Clutch on page 344.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil 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.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 332
for the location of the engine oil dipstick.
1. Turn off the engine and give the oil several
minutes to drain back into the oil pan. If you do
not do this, the oil dipstick might not show the
actual level.
2. Pull out the dipstick and clean it with a paper
towel or cloth, then push it back in all the way.
Remove it again, keeping the tip down, and
check the level.
333

{CAUTION:
Operating the engine with the air
cleaner/lter off can cause you or others
to be burned. The air cleaner not only
cleans the air; it helps to stop ames
if the engine backres. If it is not there
and the engine backres, you could be
burned. Do not drive with it off, and be
careful working on the engine with the
air cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre
can cause a damaging engine re. And, dirt
can easily get into your engine, which will
damage it. Always have the air cleaner/lter
in place when you are driving.
Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
A good time to check your automatic transmission
uid level is when the engine oil is changed.
Change the uid and lter at the intervals listed in
Additional Required Services on page 444, and
be sure to use the transmission uid listed in
Recommended Fluids and Lubricants on page 452.
How to Check Automatic
Transmission Fluid
Because this operation can be a little difficult, you
may choose to have this done at the dealer/retailer
service department.
339

If you do it yourself, be sure to follow all the
instructions here, or you could get a false
reading on the dipstick.
Notice:Too much or too little uid can
damage your transmission. Too much can
mean that some of the uid could come out
and fall on hot engine parts or exhaust system
parts, starting a re. Too little uid could
cause the transmission to overheat. Be sure
to get an accurate reading if you check
your transmission uid.
Wait at least 30 minutes before checking the
transmission uid level if you have been driving:
When outside temperatures are
above 90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should be
at normal operating temperature, which is
180°F to 200°F (82°C to 93°C).Get the vehicle warmed up by driving about
15 miles (24 km) when outside temperatures are
above 50°F (10°C). If it is colder than 50°F (10°C),
drive the vehicle in THIRD (3) until the engine
temperature gage moves and then remains
steady for 10 minutes.
A cold uid check can be made after the vehicle
has been sitting for eight hours or more with
the engine off, but this is used only as a reference.
Let the engine run at idle for ve minutes if
outside temperatures are 50°F (10°C) or more.
If it is colder than 50°F (10°C), you may have
to idle the engine longer. Should the uid level be
low during this cold check, you must check the
uid hot before adding uid. Checking the uid
hot will give you a more accurate reading of
the uid level.
Checking the Fluid Level
Prepare your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the
shift lever in PARK (P).
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3. With your foot on the brake pedal, move the
shift lever through each gear range, pausing
for about three seconds in each range.
Then, position the shift lever in PARK (P).
4. Let the engine run at idle for three minutes
or more.
Then, without shutting off the engine, follow
these steps:
1. Flip the handle up and then pull out the
dipstick and wipe it with a clean rag or
paper towel.
The automatic
transmission dipstick
handle with this symbol
on it is located in the
engine compartment
on the passenger’s
side of the vehicle.
SeeEngine Compartment Overview on
page 332for more information on location.
2. Push it back in all the way, wait three seconds
and then pull it back out again.3. Check both sides of the dipstick, and read
the lower level. The uid level must be in the
COLD area, below the cross-hatched area, for
a cold check or in the HOT or cross-hatched
area for a hot check. Be sure to keep the
dipstick pointed down to get an accurate
reading.
4. If the uid level is in the acceptable range,
push the dipstick back in all the way; then
ip the handle down to lock the dipstick
in place.
341

How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission uid to use. See
Recommended Fluids and Lubricants on page 452.
Add uid only after checking the transmission
uid while it is hot. A cold check is used only as a
reference. If the uid level is low, add only enough
of the proper uid to bring the level up to the HOT
area for a hot check. It does not take much uid,
generally less than one pint (0.5 L). Do not overll.
Notice:Use of the incorrect automatic
transmission uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transmission uid listed inRecommended
Fluids and Lubricants on page 452.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push
the dipstick back in all the way; then ip 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 uid in your
manual transmission does not require changing.
How to Check
Because this operation can be a little difficult,
you may choose to have this done at your
GM dealer/retailer 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 uid can
damage your transmission. Too little uid
could cause the transmission to overheat.
Be sure to get an accurate reading if you
check your transmission uid.
Check the uid 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
ngers on the transmission case.
342

Engine Fan Noise
This vehicle has a clutched engine cooling fan.
When the clutch is engaged, the fan spins faster
to provide more air to cool the engine. In most
everyday driving conditions, the clutch is not
engaged. This improves fuel economy and reduces
fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the
fan speed increases when the clutch engages.
So you may hear an increase in fan noise.
This is normal and should not be mistaken as
the transmission slipping or making extra shifts.
It is merely the cooling system functioning
properly. The fan will slow down when additional
cooling is not required and the clutch disengages.
You may also hear this fan noise when you
start the engine. It will go away as the fan
clutch disengages.
Power Steering Fluid
The power steering uid
reservoir is located near
the front of the engine
compartment, behind
the radiator. SeeEngine
Compartment Overview
on page 332for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering uid unless you suspect there is a leak
in the system or you hear an unusual noise.
A uid loss in this system could indicate a problem.
Have the system inspected and repaired.
355