General Motors engineers have completed a 5,000-mile cross-country electric vehicle road trip, collecting critical real-world data on EV charging, range prediction, trailering performance, and hands-free driving technology, reinforcing the company’s focus on developing customer-ready electric mobility solutions.
The journey, undertaken earlier this year by three GM engineers, took them from Southeast Michigan to San Francisco and back, covering diverse terrains, climates, and driving conditions that cannot be fully replicated through simulations. The team used two pre-production electric vehicles — the Cadillac OPTIQ luxury crossover and the GMC Sierra EV pickup truck — both equipped with Super Cruise, GM’s advanced hands-free driver assistance system.
The GMC Sierra EV towed a fully loaded cargo trailer throughout the trip, enabling engineers to study how the vehicle’s range estimation system adapts under trailering conditions. According to the team, the real-time range prediction feature performed beyond expectations, accurately showing remaining battery range with and without the trailer attached.
The expedition was led by Tony Kraatz, a quality engineering manager, along with software engineers Max Schwinghammer and Chris Cline, all based near GM’s Warren Technical Center. Kraatz said the journey offered valuable firsthand exposure to real-world use cases, including navigation updates, trailering features, and Super Cruise performance in less predictable driving scenarios.
Both vehicles were equipped with advanced monitoring equipment, allowing the engineers to observe vehicle software behavior in real time. This setup proved crucial when the team identified an issue at a public DC fast-charging station, where the Cadillac OPTIQ was charging at unexpectedly slow speeds. Further analysis revealed a software error in the charger’s code, which was promptly reported and corrected by the charging network operator.
By the end of the round trip, the team had logged 2,987 kWh of energy consumption across 32 DC fast-charging stops, while Super Cruise was engaged for approximately 4,100 miles of the journey in the GMC Sierra EV, even while towing the trailer.
GM said the road test provided insights not only into vehicle performance but also into cross-industry collaboration required to support the rapid transition to electric mobility. The trip also highlighted the depth of expertise within GM’s engineering teams, particularly in software, systems integration, and real-world problem-solving.
