2017 Chrysler Pacifica minivan EPA-rated at 28 mpg highway, 22 mpg combined; stop/start and PHEV still to come
The gasoline-powered version of the 2017 Chrysler Pacifica minivan has earned a highway-cycle fuel-economy rating of 28 mpg US (8.4 l/100km) from the US Environmental Protection Agency (EPA)—a benchmark unsurpassed by any minivan on the US market and 12% better than the vehicle Pacifica replaces.
The Chrysler brand’s all-new minivan also has a calculated lifecycle Global Warming Potential (GWP) 9% less than the outgoing vehicle. GWP considers the environmental impact of fuel production and delivery, along with the implications of its consumption. FCA US LLC engineers used industry-standard software to calculate and compare the all-new Pacifica’s GWP with that of the outgoing vehicle over 124,274 miles (200,000 km) of operation.
The Pacifica’s efficiency is further reflected in its city- and combined-cycle fuel-economy ratings of 18 mpg (13 l/100km) and 22 mpg (10.7 l/100 km), respectively. The latter marks a 10% jump compared with the outgoing vehicle, while the former delivers a 5.9% gain.
Pacifica’s engine is a direct descendant of the Pentastar V-6, named three times to the prestigious list of Ward’s 10 Best. The redesigned V-6 gasoline engine delivers a best-in-class 287 horsepower (214 kW) and 262 lb-ft (355 N·m) of torque.
Enhancements such as two-step variable-valve lift (VVL), cooled exhaust-gas recirculation (EGR) and innovative weight-reduction strategies boost the engine’s efficiency and performance, while preserving smoothness.
Increased fuel efficiency was a key impetus in the development of the redesigned 3.6-liter Pentastar V-6 engine. FCA US powertrain engineers identified the combination of features that deliver the greatest benefits in the widest operating range.
The two-step VVL system is designed to remain mostly in low-lift mode until the customer demands more power; then it responds by switching to high-lift mode for improved performance.
In addition to the obvious emissions-reduction benefits, the cooled EGR system further cuts pumping losses and enables knock-free operation at higher, real-world loads.
Pumping losses are again targeted with the engine’s upgraded variable-valve timing (VVT) system, which moves to torque-driven cam-phasing, and reduces oil demand.
The new VVT system also increases its range of authority to 70 degrees from 50 degrees. This helps mitigate knock during hot starts and expands the operating envelope of engine stop-start (ESS), a fuel-saving feature that is carried over from the previous-generation 3.6-liter Pentastar engine.
A new VVT system calibration helps deliver more torque more quickly to leverage the benefits of the new intake manifold’s longer runners. The result is a torque boost of more than 10.9% on the new Chrysler Pacifica. This occurs between 2,000 and 4,000 rpm—engine speeds most customers see frequently.
The redesigned 3.6-liter Pentastar V-6 engine benefits from numerous upgrades, which better harness the combustion event for improved efficiency. Most notably, the engine’s compression ratio jumps to 11.3:1 from 10.2:1, compared with the engine’s previous iteration.
High-tumble intake ports combine with shrouded valves to take advantage of the engine’s new fuel injectors. Featuring eight holes each, twice the number in the previous iteration’s injectors, the intake ports offer optimized atomization and targeting.
Factor in the effect of 100-millijoule high-energy ignition coils with platinum spark plugs and the above combustion enhancements account for a 1.5% improvement in fuel economy.
Multiple friction-reduction strategies contribute to an additional 1% fuel-economy hike, compared with the engine’s previous iteration.
Particularly notable is the use of HG-R1 on the timing drive guide-faces. The new Pentastar is the first production engine to feature this low-friction material. Also contributing to friction reduction are new valve springs, low-tension piston rings and piston pins, which feature diamond-like carbon coating.
The integrated exhaust manifold contributes to packaging efficiencies that enable plug-and-play-type integration across a range of vehicle segments and drivetrain configurations. The new intake manifold improves airflow, which benefits volumetric efficiency and enables a boost up to 287 horsepower.
During engine development, FCA US powertrain engineers were challenged by the potential negative effects of incremental weight, wrought by the engine’s new feature content. However, component redesign produced an engine that weighs only 326 pounds (148 kg) in the all-new Chrysler Pacifica. That’s four pounds less than the previous generation 3.6-liter Pentastar engine, despite the addition of new content weighing 13 pounds.
A thin-wall strategy was used to reduce the nominal thickness of certain die-cast components without compromising noise, vibration and harshness (NVH) characteristics.
Windage-tray weight was slashed by 19% and front-cover weight was cut by 5%. The oil pan was redesigned from a two-piece to a single-piece pan and the sump was reduced from a 6-quart fill to a 5-quart fill—resulting in an overall 5-pound weight savings compared with the previous generation Pentastar V-6 engine.
The engine’s crankshaft main bearings and pins were trimmed, which contributed to an overall block-assembly weight reduction of six pounds. This generates additional friction reduction.
Mated to the upgraded engine is the newest member of the FCA US TorqueFlite transmission family. The first nine-speed automatic ever featured in a minivan, it benefits from a wide, 9.81 ratio spread and a unique calibration designed to deliver outstanding vehicle launch characteristics, smooth shifts and overall enhanced fuel efficiency.
The nine-speed gearbox benefits from a unique calibration and an ergonomic rotary dial electronic shifter located on the vehicle’s integrated center console.
The 4.70 first gear ratio ensures an excellent launch character that has been tuned specifically to the new Pacifica. Small ratio steps for mid-range gears ensures quick, smooth transitions between gears. In higher gears, overdriven gear ratios lower engine speeds, and in turn, enhance fuel efficiency.
With its superior gear and ratio spread, the TorqueFlite nine-speed automatic transmission benefits from a compact design. It is sized similar to—and in many cases smaller than—its traditional six-speed counterparts. It’s this sizing that enables its application on vehicles such as the new Chrysler Pacifica.
The compact design is enabled by:
“Nested” carrier configuration that ensures gear sets are optimally packaged;
Incorporation of dog clutches rather than traditional and large-diameter “friction discs,” in some locations. As a result, some gear-shifts are handled via male-to-female spline engagement (similar to a manual transmission). This “friction-less” clutch system yields both efficiency and packaging benefits
The 2017 Chrysler Pacifica features a light, yet stiff unibody structure based on an all-new FCA vehicle architecture developed specifically for the global minivan front-drive E-segment. The Pacifica utilizes approximately 22% more high-strength steel than its predecessor, of which 48% is advanced high-strength steel for maximum stiffness and strength and optimal weight efficiency.
The Chrysler Pacifica is nearly 250 pounds (113 kg) lighter than its predecessor, while featuring torsional rigidity that is twice that of any current competitor.
The all-new minivan benefits from other light-weight materials. Its magnesium cross-vehicle instrument-panel beam affords greater stiffness without adding weight. The inner structure of the new minivan’s liftgate marks the industry’s first high-volume application of magnesium of this kind.
Further, the 2017 Pacifica benefits from a drag co-efficient of .300, which is best among its primary competitors.
Engine Stop-Start (ESS) technology will arrives in the market later, followed in the second half of the year by the Pacifica Hybrid—industry’s first electrified minivan. (Earlier post.) The latter will deliver an estimated range of 30 miles solely on zero-emissions electric power, and in city driving, it is expected to achieve an efficiency rating of 80 miles per gallon equivalent (MPGe) based on US EPA standards.
The Pacifica Hybrid model pairs an FCA US-patented dual-motor electrically variable transmission (EVT) with a specially modified version of the upgraded 3.6-liter Pentastar V-6 gasoline engine that features an Atkinson cycle combustion system.