The big news is that there are now two engine options: the 262-horse, 3.5-liter Duratec 35 V-6, last year's only source of power in the Flex, is now the base engine. (Those who buy the SE or front-drive SEL or Limited get the Duratec.) As far as base engines go, this one's no slouch, getting the Flex to 60 mph in 8.5 seconds. Optional motivation is now provided by a 355-horsepower, 3.5-liter EcoBoost twin-turbo direct-injection V-6 (essentially the same configuration that's made its way into the Lincoln MKS and MKT). It also offers 350 pound-feet of torque at an impressive 1500 rpm, with a fairly flat torque curve. Ford gave an "about" 7.0-second 0-to-60-mph acceleration time for the Flex with EcoBoost. Shows what 93 extra horses will do.
This engine serves as the premium option, available only with all-wheel drive and it's an option only in the SEL or Limited. This means someone who wants a front-drive Flex can get one for as little as $29,270, but the least expensive Flex with EcoBoost is an AWD SEL, costing $36,890. The EcoBoost sits in the engine lineup where an optional V-8 would've been -- except unlike stepping up to the added power of a V-8 from, say, a V-6, there is no fuel-economy penalty, and it'll run on regular gas. Whether Flex buyers choose the Duratec or EcoBoost, AWD Flexes get 16 mpg city and 22 on the highway. (Front-drive models get 17/24 mpg.)
2010 Ford Flex Ecoboost Rear Three Quarter
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The Duratec's six-speed automatic remains unchanged, but the version backing the EcoBoost was strengthened to handle the increased torque. Addressing complaints of only having the choice of "D" or "L" with the Duratec, the EcoBoost's transmission comes with paddle shifters accessed through a manual mode on the floor-mounted shifter. Both six-speeds have identical gear ratios.
The new engine is surprisingly smooth and does a fantastic job of getting the crossover up to speed. The EcoBoost achieves this with a feeling of confidence and strength like a V-8, and with very little of the whine or lag you'd typically associate with a turbocharged engine. The paddle shifters came in handy on grades and when passing slower vehicles and is something we hope Flex owners will use. And 93 additional horses more than makes up for the EcoBoost's 4800-pound base curb weight.
