2019 Ram 1500 eTorque First Drive: Silent Saver

This is a tricky driving impression to write. That’s because considerable engineering might has been expended to make the feature we’re here to focus on as unnoticeable as possible. That feature is a 48-volt mild-hybrid system sold by the name eTorque. It’s a pretty unsexy fuel saver that may prove to be a tough sell given that it adds $1,450 to the cost of a 5.7-liter Hemi V-8 and does not include any outward cues to show Mother Earth and your neighbors that you care. Sure, it buys a quite noticeable 2-mpg bump in city and combined fuel economy, which the EPA reckons will save drivers $300 per year, but can internal satisfaction and a 4.8-year payoff really move the metal (and the CAFE score)?

Naturally the PR team wants us to notice eTorque. It’s proud that Ram will be first to market in North America with a 48-volt hybrid, especially given the company it’s narrowly beating to market—Audi’s A7/A8 and several Mercedes models with a forthcoming 3.0-liter inline six-cylinder engine. But while an EcoDiesel declares its economical intentions plenty audibly, eTorque is silent and seamless. So vehicle electrification manager Brian Spohn came to coach us for 20 minutes on ways to feel the system working.

Basically, all systems like this replace the conventional alternator with a more robust motor/generator that recovers energy during deceleration and reuses that energy to restart the engine and get the truck moving after an auto-stop event (almost unnoticeably), to add torque during shifts or during transitions in and out of four-cylinder operation mode (making both less noticeable). Rarely does it contribute anything to a jackrabbit stoplight sprint, and it never assists when the engine is operating near its horsepower or torque peak, which is why the e-motor’s output (16 hp and 130 lb-ft for the V-8) doesn’t get added to the engine’s peak output (killing another sales-floor talking point).

Spohn showed a graph illustrating a Hemi engine’s RPM jaggedly dropping to zero for an auto-stop event without eTorque and smoothly dropping with it. Another showed the eTorque vehicle restarting and resuming forward motion much more quickly—within 70 ms. He claims that if you’re super quick off the brake and onto the gas, the eTorque can provide the first half-rotation of the tires as the engine is restarting. I may not be that quick. A feature that’s impossible to feel: When cruising, the system sometimes satisfies electrical loads by discharging the 48-volt battery instead of loading the generator. When lifting off the throttle at speed, eTorque regenerates energy while smoothing transmission downshifts, and when transitioning to the brake pedal, eTorque begins regenerating energy during what would otherwise be wasted pedal travel.

I drove two fully loaded Ram 1500 4WD Limited models back to back, one with and one without eTorque. The eTorque model’s electric regenerative braking was clearly noticeable (and not objectionable). Beyond that, I got the sense that the eTorque truck was just a bit smoother and sprightlier all the time—almost like it had a shorter axle ratio. Oops, guess what? It did. That particular Limited had the optional 3.92:1 axle; the unassisted one had a 3.21:1. Rats. What we can definitively say is that the efforts expended to make this system unnoticeable were extremely successful.

Pentastar V-6 eTorque

There’s no payoff time at all with the V-6, as eTorque comes standard on all new 2019 Rams equipped with the base engine. Such a deal! (OK, the new model is $600 more expensive than the identical base Tradesman model, but that buys some other upgrades, too.) Interestingly, the motor-generator is very different from the one on the Hemi. The V-6’s device was produced by supplier Continental, it’s rated at 12 hp and 90 lb-ft, and it mounts out in front of the engine with the pulley pointing aft. For this reason the internal cooling fans used on a typical alternator wouldn’t work, so this one is water cooled using its own dedicated coolant circuit. The V-8’s Magneti Marelli unit mounts conventionally (pulley pointing forward) near the top of the engine where air cooling works fine. As we publish this report, final EPA certification is not yet available for the V-6, but as with the Hemi, eTorque is expected to boost city and combined mpg figures by 2 or 3 mpg each. That would put it at 19–20 mpg city and 22–23 mpg highway with rear-drive.

There’s no way to conduct a relevant back-to-back test of V-6s with and without eTorque because the new truck has shed some 225 pounds and benefits from myriad other refinements relative to the unassisted Ram 1500 “Classic” V-6. (Note that “Classic” models will be produced concurrently for at least the remainder of this year, and this will be the only way to get a two-door regular cab Ram during that time.) I drove a base Tradesman and a fancier 4×4 Big Horn model, and both seemed to accelerate briskly and smoothly. Relative to the V-8, this powertrain is programmed to rev a bit more. Even light-throttle acceleration sees the tach regularly swinging up to 2,000 or 3,000 rpm whereas the torquier V-8 would be loafing along below 2,000. So it works a little harder but gets you there just as quickly—at least when unloaded. Auto stop/start events are just as smooth and unobtrusive as they are in the Hemi eTorque.

For those with modest payload and towing needs, this far thriftier V-6 is worth a long, hard look.

2019 Ram 1500 (eTorque)
BASE PRICE	$33,390-$60,935
VEHICLE LAYOUT	Front-engine, RWD/4WD, 5-6-pass, 4-door truck
ENGINES	3.6L/305-hp/269-lb-ft DOHC 24-valve V-6 plus 12-hp/90-lb-ft electric motor, 305 hp/269 lb-ft comb; 5.7L/395-hp/410-lb-ft OHV 16-valve V-8 plus 16-hp/130-lb-ft electric motor, 395 hp/410 lb-ft comb
TRANSMISSION	8-speed automatic
CURB WEIGHT	4,850-5,400 lb (mfr)
WHEELBASE	140.5-153.5 in
LENGTH X WIDTH X HEIGHT	228.9-241.8 x 82.1 x 75.7-79.7 in
0-60 MPH	5.9-8.5 sec (MT est)
EPA CITY/HWY/COMB FUEL ECON	17-19/22-26/19-22 mpg (est)
ENERGY CONSUMPTION, CITY/HWY	177-198/130-153 kW-hrs/100 miles (est)
CO2 EMISSIONS, COMB	0.90-1.02 lb/mile (est)
ON SALE IN U.S.	Currently

eTorque Tech Highlights

Alternators only draw modest power from the accessory drive, but eTorque’s motor-generators use the belt to slow and accelerate these big trucks, so the belt must be larger (eight ribs, up from six), stronger, and must wrap farther around the pulley than on most alternators. It also requires a tensioner on both sides to keep things tight as it transitions from generating to motoring. The eTorque Hemi also gets a larger crankshaft pulley that improves the motor/generator’s leverage on it. Belt routing is designed to shed water before it reaches the e-machine, and if slippage is detected, input/output demands are curtailed until the belt dries. This belt is designed to last the useful life of the truck—10 years/150,000 miles minimum. The V-8 eTorque system uses a separate belt for the water pump.

LG Chem provides the 12 pouch-style battery cells that comprise the 30-pound briefcase-sized 430-watt-hour battery pack. It mounts against the back wall of the cab and includes a DC-to-DC converter to satisfy the regular electrical loads and charge the 12-volt starter battery. The system only ever utilizes 130 watt-hours of that capacity to ensure it lasts the life of the truck. Speaking of mass, the whole eTorque system adds 90 pounds to a Hemi and 120 to a Pentastar V-6 (the water-cooling circuit accounts for the difference).

Fun fact: Work on these systems originally began for an application on the now dearly departed 200 model four-cylinder sedan. The Wrangler’s eTorque system is most closely related to the Pentastar V-6’s and is also provided by Continental.

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