One truck was reportedly dismantled for parts, while the other 30 were sold off internally to GMC staff ... For now, the classic Syclone remains a unicorn without an imminent successor.

The GMC Sierra 1500HD was first introduced as a heavy-duty crew cab truck in 2001. For 2007, the Sierra 1500HD resided as part of the GMC brand’s Classic line of trucks based on the outgoing GMT800 ...