The Chevrolet G20 was a full-sized van produced by General Motors

General Motors

General Motors Company , commonly known as GM, formerly incorporated as General Motors Corporation, is an American multinational automotive corporation headquartered in Detroit, Michigan and the world's second-largest automaker in 2010...

 and for a while became the staple of the North American van fleet.

The G20 and its counterparts replaced the original Chevrolet Corvair

Chevrolet Corvair

-First generation :The 1960 Corvair 500 and 700 series four-door sedans were conceived as economy cars offering few amenities in order to keep the price competitive, with the 500 selling for under $2,000...

 Greenbrier Van in the late 60s the model line evolved until it was replaced in 1996 by the Chevrolet Express

Chevrolet Express

The Chevrolet Express and GMC Savana are full-size vans from General Motors. They replaced the Chevrolet Van and GMC Vandura in 1996. The Express and Savana currently hold 44.8% of the full-size van market in the United States, just behind rival Ford's E-Series...

. 1964-70 G20s came with six-lug wheels (6 lugs - 5.5" (139.6 mm) bolt circle), while the 1971-96 generation came with the 5 lug - 5" (127 mm) bolt circle.

G20s were fitted with the ball joints from the Chevrolet/GMC 3/4 and 1 ton pickups although using the 1/2 ton pickup's brake rotors.

A light duty version, the G10, was produced alongside the G20 - the early versions used the Chevrolet passenger car wheels (5 lugs - 4.75" (120.7 mm) bolt circle) until 1975 (G10s manufactured prior to the 1976 model year had the smaller bolt pattern, common with the short wheelbase vans), yet can still handle LT tire sizes for better handling and stability.