1993 GMC SIERRA Owners Manual

Loading Your Vehicle
The CertificationKire label is found on the rear edge of the driver’s door or in
the incomplete vehicle document in the cab. The label shows th\
e 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
GWVR includes the weight of the vehicle, all occupants, fuel and
cargo.
The CertificationKire 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+
.. , - :I. -I lrT1 I I -
Never exceed the GVWR for your vehicle, or the Gross, Axle Weight Rating-
(GAWR) for either the front or rear axle.
And,
if you do have a heavy load, you should spread it out.
. -1 r,
In the case of a sudden stop or collision, things carried in the bed of 7
injuring you and others. If you put things in the bed of your truck,
you should make sure they are properly secured.
r! your truck could shift forward and come into the passenger are\
a,
-
6-67
ProCarManuals.com

Service & Appearance Care
A Do not load your vehicle any heavier than the GWR or the
- b maximum front and rear GAWRs. If you do, parts on your vehicle
can break, or it can change the way your vehicle handles. These
could cause you to lose control.
Also, overloading can shorten the
life
of your vehicle.
Using heavier suspension components to get added durability migh\
t not
change your weight ratings. Ask your dealer to help you load \
your vehicle the right way.
.,ur warranty does
nnt cover par nr componentg that fail becausl
overloading.
If you put things inside your vehicle-like suitcases, tools, packag\
es, or
anything else-they will go as fast as the vehicle goes. If you have to stop
or turn quickly, or if there is a crash, they’ll keep going.
* Things you put inside your vehicle can strike and injure peopl\
e in a
9 Put things in the cargo area of your vehicle. Try to spread the
9 Never stack heavier things, like suitcases, inside the vehicle so
d sudden stop or turn, or in a crash.
weight evenly.
that some
of them are above the tops of the seats.
When you
carry something inside the vehicle, secure it
whenever you can.
Don’t have a seat folded down unless you need to.
6-68
ProCarManuals.com

.;
Trajlering Package
PO339
If your vehicle comes with the Trailering Package, there is also 8 load rating
which includes the weight
of the vehicle and the trailer it tows. This rating is
called the Gross Combination Weight Rating (GCWR).
When you weigh your trailer, be sure
to include the weight of everything you
put in it. And, remember to figure the weight
of the people inside as part of
your load.
Your dealer can help you determine your GCWR.
Add-on Equipment
When you carry removable items, like snow plow. blades, you may need to
put a limit on how many people you carry inside your vehicle. Be sure to
weigh your -vehicle -before you buy and install the new equipment.
~____~~.. . __ ~
Your warranty doesn’t cover parts or components that fail because of
~ overloading. I
6-69 ..
ProCarManuals.com

,. *.
’
Service & Appearance Care
Truck-Camper Loading Information
Open your glove box door and look for this label:
PO338
This label will tell you how much of a load your vehicle can carry, and how
to spread out your load the right way.
Also, it will help you match the right
slide-in camper to your vehicle.
When you carry a slide-in camper, the total cargo load
of your vehicle is the
weight of the camper,
plus
everything else added to the camper after it left the factory;
everything in the camper; and
all the people inside.
I ne Cargo Weight Rating (CWR) is the maximum weight of the l\
oad your
vehicle can carry. It doesn’t include the weight of the people inside. But, you
can figure about
150 pounds for each seat.
ProCarManuals.com

The total carqo load must not be more than your vehicle’s CWR.
TRUCK LOADING INFORMATION
--7 c ‘nl
1. Recommended location for cargo
center of gravity for cargo weight
rating (Pickup Truck).
Note: Use rear edge
of load floor
for measurement purposes.
EXAMPLE OF PROPER TRUCK
AND CAMPER MATCH
I
PO484
The camper’s center of gravity should fall within the center of gravity zone for
your vehicle’s cargo load.
1. Camper center of gravity,
2. Recommended center of gravity
* Refer to Truck Camper Loading
location zone.
Information label in glove
box for
“A” and “8” dimensions.
You must weigh any accessories or other equipment you add to your vehicle.
Then, subtract this extra weight from the CWR. This extra weig\
ht may shorten
the center of gravity zone for your vehicle. Your dealer can help you with
this.
If your slide-in camper and its load weigh less then the CWR, the center of
gravity zone for your vehicle may be larger.
Your dealer can help you make a good vehicle-camper match. He’ll \
also help
you determine your CWR.
After you’ve loaded your vehicle and camper, drive to a weigh station and
weigh on the front and rear wheels separately. This will tell you the loads on
your axles. The loads on the front and rear axles shouldn’t\
be more than
either of the GAWRs. The total of the axle loads should not be more than
the GVWR.
Open your driver’s door and look at the Certificationnire label
to find out your
GWAR and GVWR.
If you’ve gone over your weight ratings, move or take out some\
things until
all the weights fall below the ratings. Of course, you should always tie down
any loose items when you load your vehicle or camper.
When you install and load your slide-in camper, check the manufacturer’s
instructions.
6-7 1
ProCarManuals.com

Service & Appearance Care
Trailer Recommendations
You must subtract your hitch loads 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, see “Trailer Towing” in the Index.
If you want more information on curb weights, cargo weights, cargo wei\
ght
rating and the correct center of gravity zone for your vehicle, your dealer can
help you. Just ask for a copy of “Consumer Information, Truck-Cam\
per
Loading.”
Pickup Conversion lo. Chassis Cab
General Motors is aware that some vehicle owners may consider having the
pickup box removed and a commercial
or recreational body installed. Before
you do
so, first contact the GM Zone Office for your area for information on
such conversions. (See the “Warranty and Owner Assistance”\
booklet for
Zone Office.) Owners should be aware that, as manufactured, th\
ere are
differences between a chassis cab and a pickup with the box r\
emoved which may affect vehicle safety. The components necessary to adapt the pickup to
permit its safe use with a specialized body should be installed by a bod\
y
builder in accordance with the information available from the Z\
one Office.
Tires
We don’t make tires. Your new vehicle comes with high quali\
ty tires made by
a leading tire manufacturer. These tires are warranted by the \
tire
manufacturers and their warranties are delivered with every new \
vehicle.
If
your spare tire is a different brand than your road tires, you will have a tire
warranty folder from each of these manufacturers.
6-72
ProCarManuals.com

I CAUTION
Poorly maintained and improperly used tires are dangerous.
Overloading your tires can cause overheating as a result of too
much friction. You could have an air-out and a serious accident.
See “Loading Your Vehicle” in the Index:
The resulting accident could cause serious injury. Check all tires
frequently
to maintain the recommended pressure. Tire pressure
should be checked when your tires are cold.
Overinflated tires are more likely to be cut, punctured, or broken
by sudden impact, such as when you hit a pothole. Keep tires
at the recommended pressure.
Worn, old tires can cause accidents; If your tread is badly worn,
or if your tires have been damaged, replace them.
Even if it’s legal, don’t drive over 85 mph (1 35 kmlh) if you
have
16 inch tires. With 19.5 inch tires, don’t drive over 75 mph
(1 20 km/h).
Underinflated tires pose the same danger as overloaded tires.
See “Special Tire Inflation” in this section for more information on
I loading and inflation pressures at speeds above 65 mph (105 kmlh). I
Inflaiion-Tire Pressure
The Certification/Tire label which is on the rear edge of the driver’s door, or
on the incomplete vehicle document in the cab, shows the corre\
ct inflation
pressures for your tires, when they’re cold.
“Cold” means your vehicle has
been sitting for at least three hours or driven no more than
a mile.
You can operate some vehicles at reduced inflation pressures only w\
hen you’ll
be carrying reduced loads. On those vehicles, the minimum cold \
inflation
pressures for a typical reduced load are printed on the “Improved Ride Tire \
Pressure” label located on the driver’s door. Weigh the v\
ehicle
to find the
load on each tire and see the label
for the minimum cold inflation pressures
for that load.
6-73
ProCarManuals.com

Service & Appearance Care
When to Check: Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
How to Check: Use a good quality pocket-type gage to check tire pressure.
Simply looking at the tires will not tell you the pressure, e\
specially
if you
have radial tires-which may look properly inflated even if they\
’re
underinflated.
If your tires have valve caps, be sure to put them back on. They help
prevent leaks by keeping out dirt and moisture.
Special Tire Inflation
If you have 16 inch tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (1 05 km/h) to 75
mph (120 kmlh) where legal, inflate tires 10 psi (70 kPa) more than
the recommended cold inflation pressure.
- You’ll be driving for very long at speeds of 76 mph (120 kmlh) to 85
mph (1 35 km/h) where legal, cold inflation pressure should be
increased by
10 psi (70 kPa) and you must also reduce axle load
capacity by
10%. Do not drive over 85 mph (135 kdh) even if
it’s legal.
6-74
ProCarManuals.com