The GMC G Series is the van made by General Motors for the US market. It is the same class of van as the Ford E Series. It was first released in 1961 and is still being produced today.
With its “Vortec” engine, 4.3L V6 (and a 6.5L diesel engine counterpart), this model is very powerful and very widely used, mostly as a school bus conversion in the US. Also, the G20's low upkeep cost, fuel economy, size, and options have made this van popular with all different kinds of trades.