Toyota sales climbed 18.4% in August to 231,537 units, compared with year-ago, giving the auto maker its best U.S. volume since May 2008, WardsAuto data shows.

Toyota for the second straight month edged out Ford, which delivered 216,017 units, making it the No.2 best-selling auto maker behind General Motors.

“We’re very optimistic for the rest of the year,” Bill Fay, group vice president-Toyota Div., tells media today in a conference call. “Part of our success, like the rest of the industry, is the strength of the industry.”

Fay, along with other industry-watchers, is predicting a 16.1 million seasonally adjusted annual rate on expected August U.S. light-vehicle sales of 1.5 million units.

Having the Labor Day weekend fall at the end of August was greatly beneficial to Toyota’s sales, Fay says, as was an extra selling day in the month. Toyota was the top retail brand last month, he says, with just a 2% fleet mix due to the typical model-year changeover in late summer.

Toyota’s core models, both the hybrid and non-hybrid versions of the Camry, posted August increases of 18.8% and 17.3%, respectively.

Through the year’s first eight months, Toyota was comfortably ahead in the U.S. midsize-car- sales race, with 287,119 Camry deliveries. Honda followed with 256,926 units of the Accord.

Prius sales, which had a rough start earlier this year, rose across the board in August. The original Prius liftback and V wagon combined for 20,089 units, up 16.4% from year-ago, while the Prius Plug-In soared 65.0%. Deliveries of the compact Prius C surged 54.1%.

Despite last month’s strong performance, the liftback and the V were the only Prius variants not in the black through August, down a combined 1.0% from like-2012.

Toyota’s redesigned Avalon continued to sell well, with the gasoline-engine-only model posting the biggest increase of any Toyota, Lexus or Scion model last month, up 161.4%. A 105.3% spike in Yaris sales was due to fleet deliveries, Fay says.

Some Toyota SUVs posted weak results in August, as did the Tundra fullsize pickup truck and Venza cross/utility vehicle. But a 43.1% jump in RAV4 sales (excluding 231 electric models), and a more than 20% increase in Tacoma compact pickups and Sequoia large SUVs offset those declines.

Lexus enjoyed its best month of 2013, up 23.0%, says Steve Hearne, vice president-sales.

The ES 300h hybrid saw the largest increase of any Lexus model, up 85.7%. The IS 250 and 350 followed closely, up 80.4%.

Hearne says IS buyer demographics are heading in the direction Lexus wants. The ’14 model has a higher percentage of male buyers and younger buyers, as well as a bigger mix of F-Sport-grade sales, compared with the ’13 model.

Other Lexus models improving in August included the CT 200h, GS 350, LS 430/460 and RX 350, the latter being the only Lexus light truck to see sales rise in the month.

Scion sales slipped 3.9%, with the FR-S still trailing year-ago. The brand’s 4.1% loss in August followed July’s 6.0% year-on-year drop. However, the Scion sports car led in volume, with 1,902 units.

A refresh seemed to motivate tC coupe deliveries last month, up 3.2%, and sales of the xD grew 8.0% from year-ago.