2021 Gmc Sierra 1500 Carbon Pro Cargo Capacity, Transmission Changes – Using the new age group of the particular pickup truck available for 2021 year, the 2021 GMC Sierra 1500 is actually not delivering lots of upgrades. The forthcoming model may not have as several choices as we may like, hence this may be a section in which the vehicle could possibly develop. Extra features and probably added trim amounts are all we can easily receive the 2021 model.