It can be configured in dozens of ways, but the GMC Sierra still isn't quite as comfortable as its direct competitors, though the interior quality continues to be a high point for the current model.
Three different body styles are available, with the standard Regular Cab having very little space behind its front seats for anything other than narrow objects. The Extended Cab gets a bit more room--enough for gear and tools--and a pair of rear-hinged access panels to make that space more accessible. Sierra Crew Cabs have four front-hinged doors that can accommodate up to six passengers.
Generally, the Sierra's flat, wide front seats offer plenty of room for even the largest of drivers, though they're lean on lateral support. Six-passenger versions have a higher, more workmanlike dash that leaves enough space beneath for a middle passenger to find decent leg room. The Sierra can also be configured as a five-seater, one with a large center console that splits front passenger space, while it also give the dash a more upscale appearance. Big controls and clear displays make the Sierra's climate and audio systems easy to decipher.In back, there's less good news. Four-door Sierras have a bench seat with a backrest that sits too close to vertical. Long trips aren't really comfortable at all, for adults or kids. The back seat doesn't quite have the leg room of competitive four-door, full-size pickups, either, but the rear seatback does fold along a 60:40 split to preserve some cargo space as it's needed. On Hybrid models, there's no storage under the rear seat; that's where the battery pack lives.
Three different bed sizes are offered across the Sierra lineup. Crew Cabs and Hybrids tote a 5'8" bed; all versions except the Hybrid can be optioned up to a 6'6" bed. Also, all versions except the Hybrid can be fitted with a long 8-foot bed.
As with other vehicles that share the Sierra's platform, this truck has noticeably better fit and finish than prior GM pickups. Materials feel better than utility-grade, and high-end versions feel and look richer than expected. Road and wind noise is low, and the Hybrid is particularly quiet in operation.