Dearborn, Michigan --The 2017 Ford F-150 will come with an all-new 3.5-liter EcoBoost V-6 engine, and the new mill will mate exclusively to a new 10-speed automatic transmission. Though official figures are still not ready, Ford expects considerably better fuel efficiency than the current six-speed automatic and the first-gen EcoBoost engine, which has been offered in the F-150 since 2011.

The new engine really is all-new, says Ford manager for V-6 engine programs Jim Mazuchowski: The heads, block, turbochargers, and pretty much everything else are all changed, even though displacement remains 3.5 liters. The biggest change is that the new V-6 now supplements its direct injection with port fuel injection, meaning there are two injectors per cylinder. In high-load situations, both injection systems work together for maximum power, but in low-load scenarios only port fueling is used, which Ford says improves efficiency.

The two turbochargers have lighter turbines for faster spooling, and they have Ford's first use of electronic wastegate control. That means that under low-load scenarios, the engine computer can fully open the wastegates to reduce engine backpressure and pumping losses. Other efficiency measures include a roller finger-follower valvetrain and hollow camshafts that save a total of 4 pounds. Overall, the engine is "a couple pounds less" than the old EcoBoost, says, Mazuchowski, though an exact weight difference hasn't been shared.

See All 4 Photos

Ford says that horsepower for the new engine will be unchanged at 365 hp, but torque will grow 30 lb-ft to 450 lb-ft at about 2,500 rpm. That makes it the torquiest truck V-6 on sale today, even trumping the Ram 1500 EcoDiesel. Those power figures are based on regular pump gas.

The new engine will continue Ford's pattern of pushing six-cylinder truck engines, Mazuchowski said. Sixty-two percent of all F-150s sold in April had six-cylinder engines; Ford says the 3.5-liter EcoBoost, which has been on sale for five years, accounts for about 30 percent of all F-150s.

"While we're already on our second generation [turbo V-6], some of our competitors aren't even in the space yet," Mazuchowski said.

See All 4 Photos

More gears for more efficiency

The updated engine also pairs with a ten-speed automatic, which will initially launch only in 2017 Ford F-150 models with the 3.5-liter engine, as well as in the2017 F-150 Raptor, which has a higher-output version of the new 3.5 EcoBoost. Though it's well known that the automatic has been co-developed with General Motors, Ford is coy about just which parts are and are not shared. Most of the transmission internals are common between Ford and GM, for instance, but the external parts and computer controls are unique to each automaker.

The new transmission gives a wider range of gear ratios than the six-speed it replaces. First gear is shorter, with a 4.7:1 ratio, while the top three gears are overdrives, intended to improve both city and highway economy. Ford engineers acknowledge that "there will be some skip-shifting" in certain driving situations, where the transmission computer might decide not to use every single gear when accelerating or decelerating if it doesn't make sense.

See All 4 Photos

The transmission is a bit heavier than the unit it replaces (no specific number was available) but only about half an inch longer than before, meaning it pretty easily bolts into the F-150. To help save length and weight, the torque converter's lockup clutch is now integrated into the turbine.

Aside from offering more ratios, the new automatic is said to improve fuel efficiency because it has less friction than the old one. "I can't quote a number, but it's significant," says Ford manager for ten-speed transmissions Kevin Norris. "But it's measurable and significant."

In addition, the new transmission controller is programmed to be more proactive than reactive, so it can, "really adapt an event while it's happening to produce the most desirable outcome," says Norris, so each shift should be smoother and faster.

The standard stop-start functionhas a special electric fluid pump to maintain transmission pressure when the engine is stopped. That means the driver can start driving again more quickly when the engine restarts because the transmission does not have to re-engage; without that feature, transmission hydraulic pressure would fall when the engine was stopped. The stop-start system is disabled when the truck is towing or in four-wheel-drive mode.

We'll still have to wait several months to find out just what effect all these changes have on fuel efficiency when EPA testing is completed this summer. The 2017 Ford F-150 goes on sale this fall.