GMC 2005 Canyon - Manual (Page 295)

Then, follow these steps:
1. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of
the filler plug hole.
3. If the fluid level is good, install the plug and be sure
it is fully seated. If the fluid level is low, add more
fluid as described in the next steps.
How to Add Fluid
Here is how to add fluid. Refer to the Maintenance
Schedule to determine what kind of fluid to use.
See Recommended Fluids and Lubricants on
page 6-13.
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough
fluid to bring the fluid level up to the bottom of the
filler plug hole.
3. Install the filler plug. Be sure the plug is fully
seated.
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