GM has published a service update for certain units of the 2023 GMC Sierra HD because the access hole cover of the torque converter housing was not installed during production, which can also be referred to as the inspection port dust cover.
The problem: the access hole cover, or inspection port dust cover, was not installed on the torque converter housing of a few 2023 GMC Sierra HD pickups at the time they were produced.
The fix: GMC dealerships are directed to install the correct access hole cover on the torque converter housing of affected 2023 GMC Sierra HD trucks. GM recommends that dealerships wait to order the necessary part until inspection confirms the fix is necessary for a truck, because very few Sierra HDs are affected.
Technicians need to raise the vehicle on a lift to access the torque converter and carry out the fix. A total of 12 minutes of labor is necessary to complete the service.
Affected vehicles may still be in dealer inventory or may have been sold to customers. The bulletin expires at the end of the New Vehicle Limited Warranty period for affected GMC Sierra HD pickups.
- Torque Converter Housing Inspection Port Dust Cover
Owners should: wait to be contacted by GM or schedule an appointment with their local GMC dealership to have the service bulletin performed. Owners who have additional questions can use the GM Customer Satisfaction Program Number and GMC customer service telephone number listed below to obtain further information if available.
- GM Customer Satisfaction Program Number: N222391310
- GMC Customer Service: 1-800-462-8782
As a reminder, the 2023 GMC Sierra HD is equipped under the hood with either the naturally aspirated 6.6L V8 L8T gasoline engine, rated at 401 horsepower and 464 pound-feet of torque, or the 6.6L V8 L5P turbodiesel Duramax developing 445 horsepower and 910 pound-feet of torque.