Most automakers saw their U.S. sales decline in the first quarter as customers feel the pinch of increasing prices and rising interest rates.

Among Detroit's two automakers to report sales Tuesday, Fiat Chrysler Automobiles NV sales fell 7.3 percent in March, pulling down first-quarter results by 3 percent. Meanwhile, General Motors Co.'s first-quarter sales dropped 7 percent as all four of its brands posted losses in the first three months of 2019. The Detroit automaker does not report monthly sales.

Ford Motor Co., which also recently discontinued monthly reports, will not share its first-quarter sales until Thursday.

"Sales have been chilled in the first quarter of 2019, a year which is also forecast to see sales fall below 17 million units for the first time since 2015," Stephanie Brinley, an analyst for IHS Markit said in a statement. "There remain areas of uncertainty facing U.S. consumers, including smaller tax returns for many as a result of 2018 tax reform and ongoing trade discussions."

Consumers are experiencing sticker shock as average new-vehicle prices were on pace to reach a high of $33,319 for the first quarter, according to J.D. Power. That's more than $1,000 higher than last year. Meanwhile, interest rates have sustained post-recession highs.

While the industry shows signs of cooling, Detroit's truck wars continued to heat up. Ram pulled off a rare upset, surpassing the Chevrolet Silverado in sales in the first three months of year.

Fiat Chrysler sold 120,026 Ram pickups, a 15 percent increase over the first quarter of 2018. That compares to the 114,313 Silverados that GM sold, a nearly 16 percent decrease.

But FCA's win over America's No. 2 selling truck comes with a footnote: After three quarters of growth for the new-generation 2019 Ram 1500 last year, it backslid in the first quarter of this year, falling from 66.7 percent of Ram 1500 retail sales in the fourth quarter to 61.2 percent in the first quarter of this year, according to J.D. Power data obtained by The Detroit News. The less-expensive previous-generation Ram, which FCA is still selling alongside the new model, gained retail share.

At the same time, FCA is offering hefty incentives on its trucks, outpacing most other truck brands, said Michelle Krebs, an analyst for Cox Automotive.

"The new (Ram) truck is very good and should stand on its own," Krebs said. But, she said, "We're seeing an affordability crunch in the whole market that may be happening in the truck segment, too."

GM spokesman Jim Cain attributed the sharp decline in Silverado sales last quarter to a lack of regular and double-cab pickups, which were scarce on dealer lots last quarter as GM rolled out the new models.

The 2019 Silverado and 2019 Ram 1500 both debuted at the 2018 Detroit auto show, but the two truck launches were about eight months apart. While the 2019 Ram 1500 hit dealer lots in the second quarter of 2018, 2019 Silverado production didn't start until August. And regular and full-size production of the 2019 Silverado hit full-swing in March.

“Our production launch was very smooth and crew-cab sales are brisk, especially those with premium trims,” Kurt McNeil, GM’s U.S. vice president of sales operations, said in a statement. “We look forward to improving availability of our wide range of cabs, trim series and powertrains.”

FCA's drop in March was led by an 11 percent decline in sales of its high-profile Jeep brand. The decrease came despite a 26 percent increase in sales of the highly profitable Grand Cherokee SUV, which notched its best March ever. Sales of the Wrangler fell 21 percent while the Renegade was down 24 percent. The Gladiator is on track for its in-market debut this month, the company added.

The Ram truck brand was the only FCA brand to post an increase last month, up 15 percent on a 9 percent gain for Ram's pickups.

Sales for Chrysler dropped 38 percent; all of the brand's nameplates posted sales decreases for the month, including a 35 percent drop in sales for the Pacifica minivan. FCA announced last week it is closing two plants in Ontario for two weeks this month and cutting the third shift at the Windsor Assembly Plant in September because of slowing demand for the Pacifica.

The Dodge brand slipped 6 percent, Fiat fell 45 percent and Alfa Romeo dropped 31 percent.

Over the first three months of 2019, GM’s flagship Chevrolet brand saw a nearly 8 percent drop in sales in the first quarter. GM’s other full-size pickup, the GMC Sierra, posted a 2.2 percent decline as the GMC brand dipped 4.4 percent overall.

The Cadillac brand saw sales fall 2 percent in the first quarter as all of its nameplates lost ground. Buick posted a decline of 8.7 percent.

Some automakers were able to buck the downward trend.

Subaru of America Inc. posted a 6 percent increase in sales to make March its best month ever and its 88th month of year-over-year growth. For the quarter, they were up 4.7 percent. The new Ascent SUV had its best month and the Outlook crossover sold 10 percent more vehicles in March than the previous year.

American Honda's sales rose 2 percent in the first quarter of 2019. For March, sales were up 4.3 percent from a year ago, despite Acura car sales dropping 10.3 percent. The Acura division posted a 6.4 percent increase, but sales of its TLX midsize sedan fell nearly 22 percent.

Hyundai Motor America reported a 2 percent increase in sales in March and in the first quarter. And Volkswagen of America's sales rose 14 percent in March and 2.3 percent over the first three months of the year.

Toyota Motor North America, however, posted a 3.5 percent decrease in sales in March and a 5 percent drop for the first quarter. The luxury Lexus brand was up 8.2 percent last month, while the Toyota division dropped 5.1 percent.

Nissan Group sales fell 7.2 percent in March, and sales are off 12.1 percent this year. The Nissan division was off by 5.3 percent last month, while luxury Infiniti brand sales fell more than 23 percent.

bnoble@detroitnews.com

Twitter: @BreanaCNoble