Gm has really tried to differentiate the models. the grill, interior, some of the wiring. entertainment options. base models are basically the same the upper end Cadillac escalade, Denali gmc. so hierarchy goes cadi, Chevy, gmc. so cadi gets all. Chevy gets less. gmc is last. so when a brand new model year starts it takes three years for gmc to catch up. that's why most cadi now come with rear passenger air bags and the other models do not. kinda like they are guinea pigs.