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:
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specific trailering condition and must be adjusted any time vehicle loading, trailer loading, or road surface conditions change.
Setting the Trailer Gain properly is ...
Customer Assistance for Text Telephone (TTY) Users (U.S. and Canada)
To assist customers who are deaf, hard of hearing, or speech impaired and who use Text Telephones (TTYs), GMC has TTY equipment available at its Customer Assistance Center. Any TTY user can communicat ...
How to Reinstall Engine Air Cleaner/Filter
1. Install the air cleaner filter into the air cleaner housing. The outer air
cleaner filter seal must be fitted properly in the air cleaner housing.
2. Align the air cleaner housing cover tabs to ...





