FLINT, MI—General Motors Co. plans to invest $150 million in its Flint Assembly Plant to increase production of Chevrolet Silverado and GMC Sierra heavy-duty pickups.

The automaker said the investment will enhance the plant’s conveyors and other tooling to increase production capacity. The work is expected to be completed in the first half of 2020.

No new jobs are tied to the announcement, but the plans come four months after the company said it would add 1,000 jobs at the plant to produce the next-generation pickups, which are shipping to dealers this week. Those positions have already been filled—mostly with workers coming from the Lordstown Assembly Plant in Ohio, which was idled in March, and Detroit-Hamtramck, which is to end production in January.

“We have been running flat out for five years straight building as many trucks as we could trying to meet demand, but we were constrained,” says GM President Mark Reuss. “We think our added capacity can help us take a bite out of the competition as we have a great opportunity to grow both retail and commercial business, especially in this HD business.”

GM has invested more than $1.6 billion in Flint Assembly since 2013, enabling an increase in the plant’s production capacity by about 40,000 vehicles annually, including more crew cab models and diesels.

In April, GM said it would invest $24 million in its Fort Wayne, IN, assembly plant to support increased output of trucks.