GMC 2010 Sierra - Manual (Page 519)

All except 1500 Series
A: Fill Plug
B: Drain Plug
. When the differential is cold, add enough lubricant
to raise the level from 0 (0 mm) to 1/8 inch
(3.2 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
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See Recommended Fluids and
Lubricants on page 7‑13.
Noise Control System
Tampering with Noise Control
System Prohibited
The following information relates to compliance with
federal noise emission standards for vehicles with a
Gross Vehicle Weight Rating (GVWR) of more than
10,000 lbs (4 536 kg). The Maintenance Schedule
provides information on maintaining the noise control
system to minimize degradation of the noise emission
control system during the life of your vehicle. The noise
control system warranty is given in your warranty
booklet.
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