2007 GMC SAVANA transmission

Maintenance When Trailer Towing
Your vehicle will need service more often when
you’re pulling a trailer. See the Maintenance
Schedule for more on this. Things that are
especially important in trailer operation are
automatic transmission fluid (don’t overfill), engine
oil, axle lubricant, belt, cooling system and brake
system. Each of these is covered in this manual,
and the Index will help you find 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
The optional heavy-duty trailer wiring package
includes a seven-wire harness assembly at
the rear of the vehicle and a four-wire
harness assembly under the left hand side
of the instrument panel. The seven-wire
harness assembly is taped together and
located in a frame pocket at the driver side
rear left corner of the frame.The seven-wire harness includes a 30-amp feed
wire. Both harnesses come without connectors and
should be wired by a qualified electrical technician.
The technician can use the following color code
chart when connecting the wiring harness to
your trailer and trailer brake controller.
Seven-Wire Harness
•Light Green: Back-up lamps
•Brown: Parking lamps
•Yellow: Left stoplamp and turn signal
•Dark Green: Right stoplamp and turn signal
•Dark Blue: Use for electric trailer brakes
•Red/Black Stripe: Trailer accessory
•White (heavy gage): Ground wire
Four-Wire Harness (Trailer Brake Controller)
•Black: Ground
•Red/White Stripe: Fused Battery
•Dark Blue: Trailer Brake Feed
•Light Blue: Fused Stoplamp/CHMSL
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Service........................................................ 286
Accessories and Modifications................... 286
California Proposition 65 Warning.............. 286
Doing Your Own Service Work.................. 287
Adding Equipment to the Outside
of Your Vehicle...................................... 287
Fuel............................................................. 288
Gasoline Octane........................................ 288
Gasoline Specifications.............................. 288
California Fuel........................................... 289
Additives................................................... 289
Fuel E85 (85% Ethanol)............................ 290
Fuels in Foreign Countries........................ 291
Filling the Tank......................................... 292
Filling a Portable Fuel Container............... 294
Checking Things Under the Hood.............. 294
Hood Release........................................... 295
Engine Compartment Overview.................. 296
Engine Oil (Gasoline Engine).................... 297Engine Oil Life System
(Gasoline Engine).................................. 300
Engine Air Cleaner/Filter............................ 302
Automatic Transmission Fluid.................... 303
Engine Coolant.......................................... 306
Radiator Pressure Cap.............................. 309
Engine Overheating................................... 309
Cooling System......................................... 311
Engine Fan Noise..................................... 317
Power Steering Fluid ................................. 317
Windshield Washer Fluid........................... 318
Brakes...................................................... 319
Battery...................................................... 323
Jump Starting............................................ 324
All-Wheel Drive........................................... 330
Rear Axle.................................................... 331
Front Axle................................................... 331
Section 5 Service and Appearance Care
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A. Battery. SeeBattery on page 323.
B. Radiator Pressure Cap. SeeRadiator Pressure
Cap on page 309.
C. Coolant Recovery Tank. SeeCooling System
on page 311.
D. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 303.
E. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil (Gasoline Engine) on
page 297.
F. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil (Gasoline Engine) on
page 297.
G. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 302.
H. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 317.
I. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 319.
J. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 318.Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see “Engine
Oil” in the DURAMAX®Diesel Engine Supplement.
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 296
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.
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3. Clean the engine air cleaner/filter housing.
4. Inspect or replace the engine air cleaner/filter.
Make sure that the filter fits properly into
the housing.
5. Reinstall the cover and fasten the
retaining clips.
{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
fluid level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
Additional Required Services (Gasoline Engine)
on page 402, and be sure to use the transmission
fluid listed inRecommended Fluids and
Lubricants on page 409.
303

How to Check Automatic
Transmission Fluid
Because this operation can be a little difficult, you
may choose to have this done at the 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.
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 fluid 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 fluid 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 DRIVE (D) until the engine
temperature gage moves and then remains steady
for 10 minutes.
A cold fluid 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 five 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 fluid level be low during this cold
check, you must check the fluid hot before adding
fluid. Checking the fluid hot will give you a more
accurate reading of the fluid level.
304

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).
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:
The transmission
dipstick is located near
the center of the
engine compartment
and will be labeled with
the graphic shown.SeeEngine Compartment Overview on page 296
for more information on location.
1. Flip the handle up and then pull out the
dipstick and wipe it with a clean rag or
paper towel.
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 fluid level must be in the
COLD 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 fluid level is in the acceptable range,
push the dipstick back in all the way; then
flip the handle down to lock the dipstick
in place.
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How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission fluid to use. See
Recommended Fluids and Lubricants on page 409.
Using a funnel, add fluid down the transmission
dipstick tube only after checking the transmission
fluid while it is hot. A cold check is used only
as a reference. If the fluid level is low, add only
enough of the proper fluid to bring the level up to
the HOT area for a hot check. It does not take
much fluid, generally less than one pint (0.5 L). Do
not overfill.
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 409.
•After adding fluid, recheck the fluid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
•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.
Engine Coolant
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for five years or
150,000 miles (240 000 km), whichever occurs first,
if you add only DEX-COOL
®extended life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have a
problem with engine overheating, seeEngine
Overheating on page 309.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to
−34°F (−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as
they should.
306

Engine Fan Noise
Your 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 fan is spinning
slower and the clutch is not fully engaged.
This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing,
and/or high outside temperatures, the fan speed
increases as the clutch more fully 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 partially disengages.
You may also hear this fan noise when you
start the engine. It will go away as the fan clutch
partially disengages.
Power Steering Fluid
The power steering fluid
reservoir is located in
the engine compartment
on the driver’s side of
the vehicle. SeeEngine
Compartment Overview
on page 296for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering fluid unless you suspect there is a leak in
the system or you hear an unusual noise. A
fluid loss in this system could indicate a problem.
Have the system inspected and repaired.
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