GMC 2003 Envoy - Manual (Page 290)

Hitches
li’s fimportanl lo have the corred hilch equipmeol.
Cros^winds, tanga truci;^ going by and rough roads
are a few reasons why you'll need the night hilch.
Here are som
,9 rules lo fcHlow:
• If you'll l>e pulling a trailer that, when loadecii will
weigh rriore than ^.000 lbs. (I 316 kgJ, be sure te
use a propEiy mounted, weight-distribuling
hitch and sway conirol of the proper size. This
equipment is very important for proper vaheóle
loading and good handling when you're driving
• Will you have lo make any holes in the body of
your vehicle when you inslall a iratler hitch?
It you do then be sure to seal tha holes tater whan
you remove the hitch. If you don'1 seal theiri,
deadly carbon monoxide ^CO} irom your exhaust
can gel into your vehicle. See "Carbon Monoxide".
Dirt and water can, too
Safety Chains
You should always attach chams belweun your vehicle
and your trailer. Cmas Jhe safely chains under the tongue
of the irailer to help prevent the tongue frorr> contacting
the road it it becomes separated from the hctchn
liistruclions about safety chains may be provided by Ihs
hitch manufacluror or by Ibe trailer manufacluier.
Follow the manufacturer's recammendatiori ior artaching
safety chairts and do not attach Ihem lo Ibe bumper.
Always leave just enough slack so you can turn
wilh your rig. Never allow safely chains to drag on the
ground.
Trailer Brakes
If your trailer weighs more than 1,500 lbs. (630 kg)
loaded, then It needs its own biakes = and they must
be adequate. Be sure lo read and toHow the in&lructiorrs
for tha trailer brakes
eq you'JI be able to Inslall, adjust
and mainiain them properly,
Vour trailer's brake system can tap into the vehicles
hydraulic brake system only if;
• The trailer parts can withstand 3.000 psi
fiio 650 hPa} of pressure.
" The trailer's brako systom will use less than
0r02 cubic inch (0.3 cc) of fluid from your vahicle's
master cylinder Otherwise, borfi braking systems
won't work well, 'You could even lose your brakes.
If eveiTlhing checks oul This far, then make the brake
fluid tap at the port on the master cylinder lhal
EBnds fluid lo the rear brakes. But don't use copper
tubirig for this. К you do. It will band and finally break off.
Use steel brake tubing
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