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:

    How to Check Lubricant
    To get an accurate reading, the vehicle should be on a level surface. If the level is below the bottom of the fill plug hole, located on the transfer case, the vehicle will need some lubricant ad ...

    Setting the Clock
    To set the time and date: 1. Turn the ignition key to ACC/ ACCESSORY or ON/RUN, then press , to turn the radio on. 2. Press to display HR, MIN, MM, DD, and YYYY (hour, minute, month, day, and yea ...

    Unable to Connect to OnStar Message
    If there is limited cellular coverage or the cellular network has reached maximum capacity, this message may come on. Push to try the call again or try again after driving a few miles into another ce ...