GM Wentzville Assembly Paint Shop Modernization

A construction project located in Wentzville.

A Bit About GM Wentzville Assembly Paint Shop Modernization

GM is putting up a new 28,000-square-foot building at Wentzville Assembly for one reason: the plant cannot stop making trucks while the paint shop gets rebuilt.

The $157 million investment, announced July 24, 2026, covers new paint processing equipment plus a major refurbishment of the existing paint shop at a plant that opened in 1983 and whose paint operations had, in parts, never been updated.

Project Scope

The addition is a standalone 28,000-square-foot structure rather than an in-place expansion, and that is the whole point. Phased tie-ins into a running paint shop are among the harder jobs in automotive construction. Solvent handling, booth pressurization and oven capacity all have to cut over without losing line rate. Building new alongside and then switching trades cost for continuity.

Scope covers new paint processing equipment and interior refurbishment across the existing shop. GM has not named an architect or a general contractor.

Wentzville employs more than 4,000 people. It builds the Chevrolet Colorado and GMC Canyon midsize pickups alongside the Chevrolet Express and GMC Savana full-size vans, and it is one of the few GM plants still turning out full-size vans. That makes its continuity strategically significant well beyond Missouri.

Why It Matters

GM calls this “at least a 45-year investment” in the site. That is the language of a company deciding which of its 1980s assembly plants get to see 2070.

Paint is usually the deciding capital item in that decision. It is the most expensive shop to build, the most heavily regulated on the environmental side, and the one that caps what body styles and finishes a plant can run. A plant with a current paint shop keeps getting product. A plant without one gets studied.

The $157 million is part of a broader announcement in which GM committed more than $400 million to modernize and expand two plants. For the supplier base around Wentzville, a paint shop rebuild reads as a longer signal than any single vehicle program does.