GMC Sierra 2500HD (2019) is 858 mm (33.78 inch) longer, 478 mm (18.82 inch) higher and has 1187 liters (41.92 ft3) bigger cargo space than Opel Insignia (2020).
Opel Insignia (2020) is 49 mm (1.93 inch) wider and 1093 kg (2,410 lbs) lighter than GMC Sierra 2500HD (2019).