2007 BUICK RAINIER Owner's Manual

Towing
Towing Your Vehicle
Consult your dealer or a professional towing
service if you need to have your disabled vehicle
towed. SeeRoadside Assistance Program on
page 504.
If you want to tow your vehicle behind another
vehicle for recreational purposes (such as behind
a motorhome), see “Recreational Vehicle Towing”
following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your
vehicle behind another vehicle — such as behind
a motorhome. The two most common types of
recreational vehicle towing are known as “dinghy
towing” (towing your vehicle with all four wheels
on the ground) and “dolly towing” (towing your
vehicle with two wheels on the ground and
two wheels up on a device known as a “dolly”).Your vehicle was not designed to be towed with
any of its wheels on the ground. If your vehicle
must be towed, see “Towing Your Vehicle” earlier
in this section.
Notice:Towing an all-wheel-drive vehicle with
all four wheels on the ground, or even with
only two of its wheels on the ground, will
damage drivetrain components. Do not tow an
all-wheel-drive vehicle if any of its wheels
will be on the ground.
Electronically Controlled Air
Suspension System
Your vehicle is equipped with an electronically
controlled air suspension system that automatically
keeps your vehicle level as you load and unload.
The system includes a compressor, two height
sensors, and two air springs supporting the
rear axle.
The system also has an internal clock to prevent
overheating. If the system overheats, all leveling
function stops until the system cools down.
During this time, the indicator light on the air
inator system will be ashing.
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The ignition has to be on for the system to inate,
in order to raise the vehicle to the standard ride
height after loading. The system can lower
the vehicle to the standard ride height after
unloading with the ignition on and also for up to
30 minutes after the ignition has been turned off.
You may hear the compressor operating when you
load your vehicle, and periodically as the system
adjusts the vehicle to the standard ride height.
Load leveling will not function normally with the
inator hose attached to the inator outlet.
Remove the inator hose from the outlet during
loading and unloading.
If the vehicle is parked for an extended period of
time, some bleed down of the suspension is
normal. Upon starting the vehicle, proper height
will be achieved.
Overload Protection
The air suspension system is equipped with
overload protection. Overload protection is
designed to protect the air suspension system,
and it is an indicator to the driver that the vehicle
is overloaded. When the overload protectionmode is on, it will not allow damage to the air
compressor. However, do not overload the vehicle.
SeeLoading Your Vehicle on page 330.
If the suspension remains at a low height, the rear
axle load has exceeded GAWR (Gross Axle Weight
Rating). When the overload protection mode is
activated, the compressor operates for about
30 seconds to one minute without raising the
vehicle depending on the amount of overload.
This will continue each time the ignition is turned on
until the rear axle load is reduced below GAWR.
Indicator Light
The indicator light on the inator switch in the rear
passenger compartment also serves as an
indicator for internal system error. If the indicator
light is ashing without the load leveling function
or the inator being active, turn off the ignition.
The next day turn on the ignition and check
the indicator light. The vehicle can be driven with
the light ashing, but if it is you should have
the vehicle serviced as soon as possible.
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Towing a Trailer
{CAUTION:
If you do not use the correct equipment
and drive properly, you can lose control
when you pull a trailer. For example, if the
trailer is too heavy, the brakes may not
work well — or even at all. You and your
passengers could be seriously injured.
Pull a trailer only if you have followed all
the steps in this section. Ask your dealer
for advice and information about towing a
trailer with your vehicle.Notice:Pulling a trailer improperly can
damage your vehicle and result in costly
repairs that would not be covered by your
warranty. Always follow the instructions in this
section and check with your dealer for more
information about towing a trailer with
your vehicle.
To identify the trailering capacity of your vehicle,
you should read the information in “Weight of
the Trailer” that appears later in this section.
Trailering is different than just driving your vehicle
by itself. Trailering means changes in acceleration,
braking, handling, durability and fuel economy.
Successful, safe trailering takes correct equipment,
and it has to be used properly.
That’s the reason for this part. In it are many
time-tested, important trailering tips and safety
rules. Many of these are important for your safety
and that of your passengers. So please read
this section carefully before you pull a trailer.
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If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed
limit restrictions, having to do with trailering.
Make sure your rig will be legal, not only where
you live but also where you’ll be driving.
A good source for this information can be state
or provincial police.
Consider using a sway control. See “Hitches”
later in this section.
Don’t tow a trailer at all during the rst
500 miles (800 km) your new vehicle is driven.
Your engine, axle or other parts could be
damaged.
Then, during the rst 500 miles (800 km) that
you tow a trailer, don’t drive over 50 mph
(80 km/h) and don’t make starts at full throttle.
This helps your engine and other parts of
your vehicle wear in at the heavier loads.
You can tow in DRIVE (D). You may want to
shift the transmission to THIRD (3) or, if
necessary, a lower gear selection if the
transmission shifts too often (e.g., under heavy
loads and/or hilly conditions).Three important considerations have to do
with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig.
For example, speed, altitude, road grades, outside
temperature and how much your vehicle is used
to pull a trailer are all important. It can also depend
on any special equipment that you have on your
vehicle, and the amount of tongue weight the
vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.
Maximum trailer weight is calculated assuming
only the driver is in the tow vehicle and it has all
the required trailering equipment. The weight
of additional optional equipment, passengers and
cargo in the tow vehicle must be subtracted
from the maximum trailer weight.
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Look in the following chart to nd the maximum trailer weight for your vehicle.
Vehicle Axle Ratio Max.Trailer Wt. *GCWR
2WD (L6 Engine)3.73 5,800 lbs (2 631 kg) 10,500 lbs (4 763 kg)
4.10 6,300 lbs (2 858 kg) 11,000 lbs (4 990 kg)
AWD (L6 Engine)3.73 5,600 lbs (2 540 kg) 10,500 lbs (4 763 kg)
4.10 6,100 lbs (2 767 kg) 11,000 lbs (4 990 kg)
2WD (V8 Engine) 3.73 6,700 lbs (3 039 kg) 11,500 lbs (5 216 kg)
AWD (V8 Engine) 3.73 6,600 lbs (2 994 kg) 11,500 lbs (5 216 kg)
The Gross Combination Weight Rating (GCWR) is
the total allowable weight of the completely loaded
vehicle and trailer including any passengers, cargo,
equipment and conversion. The GCWR for your
vehicle should not be exceeded.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 Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
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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. If you
have a lot of options, equipment, passengers
or cargo in your vehicle, it will reduce the tongue
weight your vehicle can carry, which will also
reduce the trailer weight your vehicle can tow. 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. SeeLoading Your
Vehicle on page 330for more information about
your vehicle’s maximum load capacity.The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight,
up to a maximum or 400 lbs (181 kg) with a weight
carrying hitch. The trailer tongue weight (A)
should be 10 to 15 percent of the total loaded
trailer weight, up to a maximum of 750 lbs (340 kg)
with a weight distributing hitch.
Do not exceed the maximum allowable tongue
weight for your vehicle. Choose the shortest hitch
extension that will position the hitch ball closest
to the vehicle. This will help reduce the effect
of trailer tongue weight on the rear axle.
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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.
Trailering may be limited by the vehicle’s ability to
carry tongue weight. Tongue weight cannot cause
the vehicle to exceed the GVWR (Gross Vehicle
Weight Rating) or the RGAWR (Rear Gross Axle
Weight Rating). The effect of additional weight may
reduce your trailering capacity more than the total
of the additional weight.
Consider the following example:
A vehicle model base weight is 5,500 lbs
(2 495 kg); 2,800 lbs (1 270 kg) at the front
axle and 2,700 lbs (1 225 kg) at the rear axle.
It has a GVWR of 7,200 lbs (3 266 kg),
a RGAWR of 4,000 lbs (1 814 kg) and a
GCWR (Gross Combination Weight Rating) of
14,000 lbs (6 350 kg).The trailer rating should be:
You can expect tongue weight to be at least
10 percent of trailer weight (850 lbs (386 kg)) and
because the weight is applied well behind the
rear axle, the effect on the rear axle will be
greater than just the weight itself, as much as
1.5 times as much. The weight at the rear
axle could be 850 lbs (386 kg) X 1.5 = 1,275 lbs
(578 kg). Since the rear axle already weighs
2,700 lbs (1 225 kg), adding 1,275 lbs (578 kg)
brings the total to 3,975 lbs (1 803 kg). This is very
close to, but within the limit for RGAWR as well.
The vehicle is set to trailer up to 8,500 lbs
(3 856 kg).
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But let’s say your specic vehicle is equipped with
some of the latest options and you have a front
seat passenger and two rear seat passengers with
some luggage and gear in the vehicle as well.
You may add 300 lbs (136 kg) to the front
axle weight and 400 lbs (181 kg) to the rear axle
weight. Your vehicle now weighs:
Weight is still below 7,200 lbs (3 266 kg) and you
may think that you should subtract 700 additional
pounds (318 kg) from your trailering capacity
to stay within GCWR limits.Your maximum trailer would only be 7,800 lbs
(3 538 kg). You may go further and think you must
limit tongue weight to less than 1,000 lbs (454 kg)
to avoid exceeding GVWR. But, you must still
consider the effect on the rear axle. Because your
rear axle now weighs 3,100 lbs (1 406 kg), you
can only put 900 lbs (408 kg) on the rear axle
without exceeding RGAWR. The effect of tongue
weight is about 1.5 times the actual weight.
Dividing the 900 lbs (408 kg) by 1.5 leaves you
with being able to handle only 600 lbs (272 kg) of
tongue weight. Since tongue weight is usually
at least 10 percent of total loaded trailer weight,
you can expect that the largest trailer your vehicle
can properly handle is 6,000 lbs (2 721 kg).
It is important that you make sure your vehicle
does not exceed any of its ratings — GCWR,
GVWR, RGAWR, Maximum Trailer Rating
or Tongue Weight. The only way to be sure you
are not exceeding any of these ratings is to weigh
your vehicle and trailer.
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