New 10-speed is a delight in the 2017 F-150

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Written by Lindsay Brooke
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Less than 200 feet after leaving my home driveway, the F-150"s transmission is already in 3rd gear. A half-block later it has upshifted into 5th. Merging into the main drag on light throttle, the transmission upshifts two gears at a time. The gear changes up and down are so seamless and hushed, I have to watch the indicator lights on the cluster to know what gear is engaged. It took perhaps five minutes of driving this 2017 Ford pickup, a King Ranch-spec crew cab with the new 3.5-L twin-turbocharged V6 and equally new 10-speed automatic, to realize this is the future for full-size truck transmissions. More ratios are better, as long as they"re calibrated as exquisitely as in this early production test truck. And 10 of them feel ideal in a 5000-lb (2268-kg) vehicle propelled by 375 SAE-rated horsepower (280 kW) and 470 lb ft (637 N m). Co-developed by Ford and GM (download the July 2016 AE feature, http://magazine.sae.org/auto/), the 10R80 carries four planetary gearsets and six clutches in an overall package that"s virtually the same size and mass as the 6-speed unit it replaces. Ten gear ratios appear to be an increasingly popular solution at other OEMS, too, as Toyota debuts its new Aisin-sourced AWR10L65 in the 2018 Lexus LC coupe and LS sedan and Honda springs its new 10-speed transaxle, developed in-house, for front drive applications (see http://articles.sae.org/15215/). With a 7.4 ratio spread and triple-overdrive ratios in gears 8, 9 and 10, the Ford 10R80 I tested was typically in 7th or 8th gear when driving on 40 mph (64 km/h) suburban Detroit roads on light throttle. First gear is numerically lower than its 6-speed equivalent, and 10th is slightly higher than the 6-speed"s 6th, with a super-close-ratio feel from the ratios in between. It"s a set-up that provides more standing-start-accel punch and slightly lower rpm in open-road cruising. Tipping into the F-150"s gas pedal for highway roll-on acceleration 65 mph (104 km/h) at 1,500 rpm the gearbox zips imperceptibly from 10th gear to 7th. Later while northbound on Interstate 75, the truck"s running at steady-state 80 mph (128 km/h) on light throttle in the indicated 10th gear, but a long hill looms ahead. Under load on three-quarter throttle, the 10R80 drops four ratios rapidly, then briefly drops two more to 4th gear at 4000 rpm before upshifting four gears as the road flattens again. Slick and impressive! The truck"s stop-start function was smooth and unobtrusive in most circumstances. But few drivers will enjoy the loss of power steering boost when the engine shuts down the wheel gets heavy immediately. Although the V6 starts instantaneously, the feeling of being stopped with a dead engine in the middle of a four-way intersection is unnerving. A few WOT drag-style starts on my favorite back road showcased the 10R80"s ease in rocketing sequentially up through the box with almost CVT-like smoothness. In such situations the transmission doesn"t skip-shift. In the 3.5-L F-150, fuel shuts off at 5750 rpm but the cals are designed to keep the V6 in its power sweet-spot under such conditions. The calibration team responsible for the F-150/10R package deserve a bonus for their thorough work how about it, Raj (Nair, Ford"s global product-development boss)? Just my opinion. Addition of the 10-speed gave F-150 a 1-mpg bump in EPA fuel efficiency for the gas V6. Will pairing it with the 3.0-L diesel V6 next year push a 2WD F-150 over the elusive 30-mpg highway threshold?



Date written: 19-Jan-2017 11:36 EST

More of this article on the SAE International Website

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