According to GMC: The First 100 Years, and GM, General Motors purchased GMC in 1909, and they didn’t get around to swallowing up Chevrolet until around 1916. Given seniority, it’s fair to say that the Silverado is junior to the Sierra. Add to that questionable logic the fact that GMC has the one thing Chevrolet doesn’t: a Denali trim, a 6.2-liter V8 and a – gasp – six-speed automatic. Other than that, the trucks are identical save for the front ends, and trace their lineage back to GM’s GMT900 line of vehicles, which includes a bunch of SUVs. Hey – it all winds up in the same corporate pie in the end, right?