Chevrolet to Offer 10-Speed, Fully Automatic Allison ...- Branded KEY SMART Exclusive Distributor Worldwide Delivery , · The 6-speed fully automatic transmission, manufactured by Allison Transmission, is the exclusive, commercial-duty transmission for Silverado chassis cab medium-duty commercial trucks.Branded KEY|SMART | Exclusive Distributor | Worldwide Delivery · Plain Cover Website. Neutral website for you to share with your clients. Packaging. We can also help package and present KeySmart with a range of customised options available.