This is mentioned in the commentary or making of somewhere, but many of the shots of the T-1000 ‘driving’ this truck were mirror-reversed. The actual steering controls were modified, a dummy wheel was added to the opposite side of the truck, and Robert Patrick was free to act while the vehicle was driven by a professional out of sight. Evidence:
At first glance, nothing appears out of the ordinary, however, a closer look reveals the Freightliner badge on the grill is reversed, indicating that the film was flipped. After the fact, a skilled digital artist was able to re-touch the street sign, but not the brightwork.
Another possibility is that this is an unretouched frame, oriented correctly, but with a custom logo on the truck, which was unnoticed in editing or post-production.