After several years of keeping quiet, Volvo is finally starting to roll out new and updated products--especially in its core mid-size segment.

We've now driven three of them, all 2015 models: the XC60 crossover utility, the S60 sport sedan, and the new V60 wagon, the first actual Volvo wagon to be sold here in a few years.

MORE: 2015 Volvo V60 - review

All of our test cars were fitted with the company's brand-new 2.0-liter four-cylinder Drive-E engine, a highly efficient new powerplant that will ultimately replace no fewer than eight different engines across Volvo's entire lineup of vehicles.

The Drive-E engine, in two different versions, powers the wheels of these three models through a new eight-speed automatic transmission.

The goal, of course, is to maintain the power and performance its customers expect, while radically improving the fuel economy delivered by a smaller, lighter engine.

MORE: 2015 Volvo XC60 - full review

Unfortunately, due to packaging constraints, the Drive-E engine is only fitted to front-wheel-drive versions of these three models.

2015 Volvo XC60

2015 Volvo XC60

Next XC90 on scalable platform

The Drive-E's first appearance in an all-wheel-drive vehicle will be in the upcoming all-new and redesigned 2015 Volvo XC90 large crossover utility vehicle, which will be unveiled this fall and likely go on sale early next year.

That new XC90 will be the first of many new Volvo models built on a Scalable Platform Architecture that can be used to underpin cars and utility vehicles of various lengths, widths, and heights with a single set of components.

Economies of scale from such scalable architectures are the only way a small carmaker like Volvo can maintain a full model range while building fewer than 1 million vehicles a year. Mazda and Subaru, among other small makers, use the same approach.

The first Drive-E variant we drove was a 240-horsepower direct-injected and turbocharged 2.0-liter four, known as the T5 (meaning a power output of roughly 250 to 300 hp). It's offered in 2015 models of the S60, V60, and XC60.

2015 Volvo S60

2015 Volvo S60

Turbo, or turbo AND super

The second and more powerful version, the T6, adds a supercharger to increase low-end power as well as the turbocharger for higher engine speeds. It puts out 302 hp.

At least for 2015, that engine is only offered in the S60 and XC60, not the V60 wagon.

Each engine provided good power in the cars we drove, but obviously the T6 is the hot rod of the two, with 0-to-60-mph acceleration of just 5.6 seconds in the S60 T6 sport sedan.

MORE: 2015 Volvo S60 - full review

Yet both engines return far better EPA gas-mileage ratings than the older, heavier engines they replaced.

In the S60, for example, the previous best EPA ratings were 24 mpg combined (21 mpg city, 30 mpg highway) with a 2.5-liter five-cylinder engine, six-speed automatic, and front-wheel drive.

The new S60 T5 Drive-E engine and eight-speed automatic bring that up to 29 mpg combined (25 mpg city, 37 mpg highway)--more than a 20-percent boost.

2015 Volvo V60

2015 Volvo V60

Similarly, in the XC60, combined ratings go from 21 mpg with a 3.2-liter six-cylinder and six-speed automatic for 2014 to 27 mpg (24 mpg city, 31 mpg highway) with the 2015 Drive-E and eight-speed combination, both in front-wheel-drive form.

Drive impressions

Our test drives over two days consisted of an XC60 T6 crossover, a new V60 T5 wagon, and then back to the T6 in an S60 sedan.

All three cars received new and sleeker front styling last year, with the new engines following for 2015. The T5-equipped cars are available now, with the T6 versions entering dealerships in June.

2015 Volvo XC60

2015 Volvo XC60

Again, these are for front-wheel-drive versions only. The T5 AWD and T6 AWD models confusingly will continue to use older, less fuel-efficient engines until these models are redesigned in two or three years.

That's because, apparently, the current cars weren't designed to accommodate the new engine and transmission AND Volvo's Haldex all-wheel-drive system. To be fair, they're now in their sixth model year--and remain fresh and stylish looking, to our eyes.

We'd not previously driven an S60 with the older engines, and the V60 wagon is a new model. But we had previously tested a Volvo XC60 crossover, in 2010, fitted with the six-cylinder engine and all-wheel drive.

The 2015 Volvo XC60 T6 in front-wheel-drive form is a considerably different car. It feels much lighter and somewhat more nimble, pulls strongly, and should deliver much better gas mileage.

We hope to test these cars over a longer period; we'll keep you posted.


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