GMC 2007 Canyon - Manual (Page 361)

If the level is below the bottom of the filler plug
hole, located on the front axle, you may need
to add some lubricant.
When the differential is cold, add enough lubricant
to raise the level to 1/2 inch (12 mm) below the
filler plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level
to the bottom of the filler plug hole.
What to Use
See Recommended Fluids and Lubricants on
page 447 to determine what kind of lubricant
to use.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 366.
For any bulb changing procedure not listed in this
section, contact your dealer.
Halogen Bulbs
{ CAUTION:
Halogen bulbs have pressurized gas
inside and can burst if you drop or
scratch the bulb. You or others could be
injured. Be sure to read and follow the
instructions on the bulb package.
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