GMC Sierra 2500HD (2015) is 1241 mm (48.86 inch) longer, 490 mm (19.29 inch) higher, 69 kg (152 lbs) lighter and has 1187 liters (41.92 ft3) bigger cargo space than Opel Insignia (2017).
Opel Insignia (2017) is 39 mm (1.54 inch) wider than GMC Sierra 2500HD (2015).