V-6 Mills Mean Big Business For Mack Plant

DETROIT – As workhorse engines go, the Pentastar V-6 is the equivalent of a Clydesdale, with sturdy variants powering 1.3 million FCA vehicles annually – a number projected to grow as V-8s vanish and V-6s gain capability and efficiency.

FCA’s Mack Avenue Engine Plant here, and its sister Trenton (MI) Engine Plant, are ground zero for Pentastar V-6 manufacturing, pumping out nearly 1 million of the company’s global Pentastar V-6 output. Most are 3.6L variants, but the family includes 3.2L and sub-3.0L versions built at the Mack plant.

Julian John, chief engineer-Pentastar engines, says the basic aluminum-block 60-degree Pentastar V-6 replaced seven engines from four engine families, with major components cut from 174 parts to 54.

The 3.6L won Wards 10 Best Engines awards in 2011, 2012 and 2013, most recently in the Ram 1500 pickup, but the engine powers 11 FCA vehicles including Jeeps, minivans, mid- and fullsize sedans, CUVs and SUVs and even cargo and delivery vans. An Atkinson-cycle version powering the ’17 Pacific Hybrid minivan received 2017 Wards 10 Best Engines accolades.

A heavily upgraded version with 80% new or revised parts and the hybrid variant are manufactured at FCA’s plant in Saltillo, Mexico. The revised engine incorporates a number of fuel-saving features such as 2-step valve lift, a variable-displacement oil pump and a cooled EGR valve. The updated engine provides an average 6% fuel-efficiency improvement (7.7% combined in the Jeep Grand Cherokee) with higher output and a 14.9% increase in low-end torque, John says.

On a recent tour, plant manager Tyree Minner notes current Pentastar V-6 machining and assembly uses only 50% of the sprawling 1.4-million sq.-ft. (130,064 sq.-m) facility’s space, leaving ample room for unspecified future work. Built in 1916 and purchased by Chrysler in 1953, the former stamping and Viper production plant has been building V-6 engines since 2011.

Pentastar V-6 production at Mack is expected to grow steadily over the coming seven years, increasing by a third to 365,000 engines annually in 2023, according to WardsAuto/AFS Powertrain Forecast data.

The plant eventually will shift to building the more-efficient 3.6L V-6 now produced solely in Mexico, and one missing piece in the company’s portfolio, a turbocharged version of the Pentastar V-6, also will add to the plant’s workload.

Brian Maxim, vice president-global powertrain forecasting for AutoForecast Solutions, predicts the Mack plant will build future direct-injection versions of the Pentastar V-6, as well as a high-performance, direct-injection twin-turbocharged variant due in mid-2018. Codenamed TV6, the turbo engine will replace a sizable portion of 5.7L Hemi V-8 volume in trucks and rear-drive cars such as the Charger and Challenger, Maxim says.

Kevin Royce, senior manager-gasoline engine engineering, declines to specify what engines might be in the Mack plant’s future or how its extra capacity might be used.

“Plans are in the works to meet our needs based on regulatory requirements,” Royce says. “We’re always evaluating alternatives for the future. We’ve looked at all the options.”

[email protected] @bobgritzinger