In 2019, Fiat Chrysler's (NYSE:FCAU) Ram brand overtook General Motors' (NYSE:GM) Chevy Silverado as the No. 2 pickup model by sales in the U.S. (Both Ram and Chevy have historically trailed Ford Motor Company's (NYSE:F) F-Series trucks in the full-size truck market.) Some pundits saw it as a rare changing of the guard in this ultra-profitable market segment.

However, the Chevy Silverado retook the No. 2 position in 2020. Moreover, including the Silverado's upscale twin -- the GMC Sierra -- GM surged past Ford as the top maker of full-size trucks in the U.S. While the market will remain highly competitive, General Motors is well positioned to maintain its lead over the next few years.

Ram falls back to third place

A year ago, Fiat Chrysler reported that Ram truck deliveries totaled 633,694 in 2019: up 18% year over year. This allowed it to easily overtake the Chevy Silverado for the No. 2 spot in the U.S. truck market. Domestic sales of the Silverado decreased 2% in 2019 to 575,600 units.

A white Chevy Silverado on a dirt road, with a green field in the background

Image source: General Motors.

The Ram brand's 2019 success wasn't a complete fluke. Fiat Chrysler has done an excellent job of elevating the brand and designing great trucks. Indeed, different variants of the Ram pickup have been named "Truck of the Year" by Motor Trend for three consecutive years.

That said, GM's trucks have hordes of fans, and brand loyalty tends to be very strong in the pickup market. General Motors executives consistently blamed the 2019 market share losses on temporary supply constraints related to the changeover to all-new full-size truck models. And GM also has the GMC Sierra in its arsenal. Including the Sierra, GM delivered 807,923 full-size trucks in 2019, beating Ram by 27%.

GM's 2020 performance in the full-size truck market validated its leaders' confidence. Domestic deliveries of the Chevy Silverado jumped 10% year over year last quarter, totaling 179,444 units: 11% ahead of Ram's 161,266 deliveries. For the full year, GM and its dealers delivered 594,094 Silverados in the U.S.: 5% better than Ram's 563,676 deliveries. Including the GMC Sierra, GM delivered 847,110 full-size trucks in the U.S. last year. Not only was that a full 50% ahead of Ram, it also pushed the General past Ford as the top full-size truck seller in the country. Ford delivered 787,422 F-Series trucks in the U.S. during 2020.

An impressive achievement in light of supply constraints

General Motors' growth and market share gains in the full-size truck market last year were particularly impressive considering how tight inventory levels were.

Every U.S. automaker faced supply constraints in 2020 due to the COVID-19 pandemic, which forced factories to halt production for much of the spring. However, GM faced an additional headwind. Due to a six-week UAW strike in the fall of 2019, it entered 2020 with lower-than-planned inventory, exacerbating the impact of the production shutdown.

Dealers figured out ways to keep truck sales up even with minimal inventory, including pre-selling trucks before they even arrived on the lot. Still, it would be reasonable to assume that sales would have been even stronger had there been no supply constraints.

More supply is coming

During 2021, GM is likely to keep its truck factories working as fast as possible to churn out Chevy Silverados and GMC Sierras. A few months ago, it increased staffing at one of its truck plants to boost monthly output by 1,000 units. Nevertheless, supply is likely to be tight for most if not all of 2021.

Relief on the supply front will come in 2022. GM is making a series of investments to restart production of the Chevy Silverado and GMC Sierra at its Oshawa plant in the Toronto suburbs in January 2022. That will coincide with the introduction of a major design refresh for the Silverado 1500 and GMC Sierra 1500 models.

In 2021, Fiat Chrysler's Ram may continue to challenge the Chevy Silverado for second place in the U.S. truck market, and Ford might have an opportunity to retake the overall title for full-size truck sales. But with inventory constraints likely to ease gradually over the course of 2021 and more production capacity coming on line in early 2022, GM is likely to widen its lead in this lucrative market segment by next year.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.