Domestic deliveries declined nearly 7% year over year for Ford Motor (NYSE:F) in January and February. The No. 2 U.S. automaker bounced back in March, though. On Tuesday, Ford reported that its U.S. deliveries rose 3.4% last month.

However, Ford's solid March performance was upstaged by a double-digit sales increase at crosstown rival General Motors (NYSE:GM). While the Ford F-Series truck lineup continued its dominant run last month, Ford is clearly suffering due to a lack of fresh products in key market segments.

F-Series trucks excel once again

In March, Ford delivered 244,306 vehicles in the United States, up from 236,250 a year earlier. Retail sales (consisting of deliveries to individual consumers and some small businesses) ticked up 0.8% to 158,996 -- helped by an extra selling day during the period -- while fleet sales rose 8.7%, mainly due to the timing of deliveries to rental car companies.

The popular (and lucrative) Ford F-Series truck lineup again accounted for a disproportionate chunk of sales last month. Domestic F-Series deliveries reached 87,011, up 7% year over year, accounting for more than 35% of Ford's total sales mix. This was the best March performance for the F-Series lineup since 2000.

A black Ford F-150

Ford continues to lean heavily on F-Series truck sales. Image source: Ford Motor Company.

Ford's freshest crossover and SUV products also sold well last month. The Ford Expedition achieved a 3.3% sales increase, despite severe supply constraints, including a 46.1% jump in retail sales. Lincoln Navigator deliveries nearly doubled year over year. Finally, deliveries of the Ford EcoSport -- which made its U.S. debut in January -- reached 3,296, surpassing its combined sales total for January and February.

However, there weren't many other bright spots for Ford. The Ford Edge posted a double-digit sales gain, and Ford's commercial van offerings sold well, but Ford's passenger car deliveries continued to plunge (down 7% year over year). Additionally, sales of the Ford Escape, the company's most popular crossover, fell for a third consecutive month.

General Motors deliveries sail higher

GM's domestic deliveries also declined modestly for the months of January and February combined, but the company turned things around in a big way during March. General Motors delivered 296,341 vehicles in the U.S. last month, up a stunning 15.7% year over year. Retail deliveries surged 13.8% to 231,156, while on the fleet side, commercial deliveries rose about 19%.

The sales strength was broad-based last month, as each of GM's four domestic brands -- Buick, Cadillac, Chevrolet, and GMC -- posted double-digit growth. Pickup sales were solid, but not at the same level as Ford, with 85,150 deliveries across the General's four pickup truck models. (Pickups accounted for just under 29% of GM's March sales mix.)

However, the real story for GM was the success of three crossovers for which it rolled out all-new versions last year: the Chevy Equinox, Chevy Traverse, and GMC Terrain. Combined deliveries of those three models surged 51%, from 41,159 to 62,142.

GM also continued to clean up in the subcompact SUV/crossover segment. It delivered a record 15,118 Buick Encores, while Chevy Trax deliveries reached 8,207. Together, these two models outsold the competing Ford EcoSport by more than seven times.

New products can't come soon enough for Ford

For several years, General Motors has been working to fill every major truck, crossover, and SUV market segment -- and keep those products fresh -- to capitalize on shifts in U.S. demand. Those efforts have paid off, particularly in the crossover/SUV market, where GM outsold Ford by about 66% last month.

By contrast, Ford has been a little slower to update its product portfolio. Car sales have fallen dramatically, but Ford has been relying entirely on its F-Series trucks to make up for the lost volume. The Escape and Explorer (Ford's two most popular crossovers by far) are both aging, and Ford hadn't expanded its U.S. crossover/SUV lineup in many years until introducing the EcoSport in January.

Ford is set to make big progress on transforming its crossover, SUV, and truck offerings over the next two years. During that period, it will revive its Bronco SUV and Ranger midsize pickup models, while the Escape and Explorer will get much-needed design updates. This will position Ford for much greater success a few years down the road.

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