Special Application Services

• Allison Transmission™ Vehicles Only: Replace external transmission filter at first engine oil change only.
• Vehicles with Dual Wheels: Check dual wheel nut torque at 160 km/100 mi, 1 600 km/ 1,000 mi and 9 700 km/6,000 mi.
• Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/ 3,000 mi.
• Have underbody flushing service performed once a year.

    See also:

    Customer Assistance Offices (U.S. and Canada)
    GMC encourages customers to call the toll-free number for assistance. However, if a customer wishes to write or e-mail GMC, the letter should be addressed to: United States GMC Customer Assistance ...

    When the System Does Not Seem To Work Properly
    The RVC system might not work properly or display a clear image if: • The RVC is turned off. See “Turning the RVC System On or Off” earlier in this section. • It is dark. • The sun or the ...

    Replacing the Engine Air Cleaner/ Filter
    1. Locate the air cleaner/filter assembly. See Engine Compartment Overview on page 10‑6. 2. Loosen the four screws on the cover of the housing and lift up the cover. 3. Remove the engine a ...