U.S. light-vehicle sales continued a steady upward climb in March, as the market posted its 31st straight increase from year-ago and first-quarter 2013’s seasonally adjusted annual rate of 15.2 million units marked the highest quarterly total in five years.

March’s results also continued trends started early in the year, including a truck-driven market share rebound for the Detroit Three.

Deliveries totaled 1.45 million light vehicles in the month, equaling a daily selling rate of 53,618 units over 27 days and outpacing March 2012’s DSR of 50,005 (28 days) by 7.2%.

The tally translates to a 15.2 million light-vehicle SAAR, down slightly from February’s 15.3 million, but well above like-2012’s 14.1 million.

The first-quarter SAAR ranks above fourth-quarter 2012’s 15.0 million and is noticeably higher than the 14.2 million total of January-March 2012. It also was the best for any quarter since the identical figure was recorded in first-quarter 2008.

As in February, cross/utility vehicles, large pickups and large SUVs provided the spark.

CUV sales increased 20.6% over year-ago, with gains made in each of the group’s segments. Large CUVs doubled year-ago’s volume on major gains from General Motors’ refreshed trio of Buick Enclave, Chevrolet Traverse and GMC Acadia. Nissan’s redesigned Pathfinder large CUV notched a 187% gain over its predecessor, and Mazda CX-9 sales were up 132%, helping more than offset a 32.5% decline for the Ford Flex.

Sales of GM’s large CUVs appeared to be petering out until the auto maker performed a mid-cycle upgrade at the end of 2012. Since then, the Lansing Delta (MI) plant, where the vehicles are assembled on three shifts, has been running steady overtime.

More significant is the uptick in industrywide sales of large and large/luxury CUV, SUVs, vans and pickups, increasing 24.2% in March. That pushed their combined market share to 18.2%, compared with year-ago’s 15.7%. Market share in the quarter for the large trucks totaled 18.4% vs. like-2012’s 16.4%.

Incentives appeared to play a part in the 17.9% surge in large-pickup deliveries, which benefited GM, Ford and Chrysler. GM’s fullsize-pickup sales increased 9.8% in March, while Ford F-Series deliveries grew 18.9% and the Ram Pickup posted a 31.4% gain.

In addition, Nissan’s Titan recorded one of its biggest spikes in a long time, up 24.9%, while the Toyota Tundra saw an 11.9% rise.

GM’s large SUVs enjoyed robust results as well, increasing 32.6% in March and 14.0% for the quarter.

Better still for GM, which racked up its third straight year-over-year market-share gain in March, were small cars. Led by the Chevrolet Cruze and new Spark, segment sales increased 17.0%. That compares with a 5.6% decline for Ford and still-soft sales of Chrysler’s Dodge Dart, which posted its best month ever at 8,091 units.

GM’s 17.0% market share represents a drop from February’s 18.9%, but it remains well above year-ago’s 16.5%. Its first-quarter penetration of 18.1% was higher than like-2012’s 17.6%.

For the third straight month, Ford also increased its share over year-ago. Chrysler, which has had 36 straight monthly volume increases, posted its fourth consecutive share increase.

For the quarter, the Detroit Three owned 45.6% of the market, compared with 44.4% a year earlier.

The first-quarter share improvement by the Detroit Three is coming mostly at the expense of Honda, Hyundai, Kia and Nissan.

Toyota wavered a little in March with its first year-over-year share decline since February 2012, but still posted its 17th consecutive sales increase. Nissan and Honda ended the quarter on stronger notes in March, but both lost share compared with year-ago during the first three months.

Nissan remains somewhat of a conundrum. More than 40% of its volume consists of new or redesigned vehicles dating back to last summer, but its sales have declined in four of the past seven months.

Honda has been maintaining sales increases, but its share declined to 9.2% in first-quarter 2013 from 9.3% a year ago.

Volkswagen/Audi boasts 42 straight year-over-year sales increases, with a 9.7% gain in March.

Hyundai and Kia, due to capacity constraints and stiffer competition in the low end of the market, combined for a sales decline of 4.3% in March and 3.4% for the quarter. A lack of large vehicles also is cutting into their shares.

hstoddard@wardsauto.com