The Sierra 1500HD was built by GMC.
Sierra 1500HD answers
When did GMC stop making the Sierra 1500HD?
GMC stopped production on the Sierra 1500HD in the 2006 model year. GMC produced the Sierra 1500HD for 5 years.
What years did GMC make the Sierra 1500HD?
The GMC Sierra 1500HD was produced from 2001 to 2006.