GMC 2005 Sierra 1500 Pickup Owner's Manual page 475

Improved Ride with Light Load
CAUTION:
{
Do not overload your vehicle or underinflate
the tires. Overloading your vehicle or
underinflating the tires can cause rapid loss of
pressure and cause a serious crash. Only use
reduced rear tire pressure when your vehicle
meets the criteria for a light load.
If you have a 1500 or 2500 Series truck with
LT245/75R16E size tires and you are operating your
vehicle under light-load conditions, you can improve ride
quality by adjusting both the front and rear cold tires
to the recommended pressure shown on the Improved
Ride label.
An example of the Improved Ride label is shown here.
This label is attached to the lower section of the
driver's door edge, for 1500 and 2500 Series trucks
equipped with LT245/75R16E size tires.
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