Serious Power in New Ram Engines

Oct. 28, 2013

One thing Chrysler’s Ram Trucks brand has been missing from its product lineup is a large-displacement gasoline V-8 that can do more work than the current 5.7-liter Hemi. Now it has one, in the 6.4-liter Hemi V-8, announced earlier this year and shown off in late September. One thing no American truck builder had was a diesel-powered light-duty pickup, and now Ram has one, with the 3-liter EcoDiesel V-6 that’s now optional in the 1500 series half-ton pickups.

Enthusiastic Ram executives showed them off at an event near Westlake Village, northwest of Los Angeles, and they really did have something to brag about. The new light-duty diesel will probably be the only one offered for about a year, when Nissan brings out its revised Titan pickup with a new Cummins 5-liter V-8 diesel.

Already you might be asking, why doesn’t Ram (and Dodge before it), which for 24 years has bragged about its highly regarded Cummins Turbo Diesel, go to Cummins for the light-truck version? Because Ram is now partly owned and pretty much controlled by Fiat of Italy, which has been using diesels from VM Motori, another Italian manufacturer, so it makes business sense for Ram to do so, too.

The V-6 EcoDiesel is a VM Motori product that’s been proven in Europe and elsewhere, Ram executives say, and it has been modified to meet American exhaust emissions standards. As with other diesels here, the EcoDiesel uses cooled exhaust-gas recirculation, a diesel particulate filter, and urea injection that’s the active part of selective catalytic reduction.

Another question would concern the engine’s small displacement of 3 liters, or 183 cubic inches. Won’t the Titan’s 5-liter, 305-cubic-inch Cummins V-8 blow its valve covers off? A few weeks after the Ram event, Cummins showed off the new diesel, and we now know that it will make up to 300 horsepower and 520 to 560 lb.-ft. in the Nissan. So it will probably haul and tow more, and if that’s important, well, wait another year to check it out. But for anyone wanting a diesel half-tonner now can rest assured this little Italian makes more than adequate power and torque numbers and really moves.

Maximum output is claimed to be 240 horsepower and 420 lb.-ft., and it felt like all of that as I ran a sharp white Ram 1500 crewcab pickup over dirt roads on a horse ranch in Ventura County, then out onto public highways—up and down hills and around sharp bends on a road that cut through the coastal mountains and skirted deep ravines on its way to the Pacific Coast Highway, then over more level back roads and urban boulevards to our base at the ranch. The diesel revs not quite as fast as a gasoline engine and is rather quiet, and with the soot and NOx wrung out, there’s absolutely no smoke or smell to the exhaust.

The standard and only transmission is the ZF-made TorqueFlite 8-speed automatic. A rotary shifter on the dash dials in P, R, N and D, while up- and down-buttons on a steering wheel spoke allow manual operation. It works better than you’d think. My thumb got really busy while moving downgrade, and I punched the tranny from 8th all the way to 4th and 3rd to help with retarding, even though the big disc brakes would’ve been more than enough on their own.

The EcoDiesel not only goes and will probably pull heavy loads with its hefty torque, but also delivers fuel economy that’s expected to be better than Ram’s current champ, the Pentastar gasoline V-6’s 23/25 city/highway MPG—said to be the best in a half-ton pickup. My run over the mountains ended with the info center in the dash reporting 26.4 mpg—pretty good if it’s accurate. A couple of other reporters said they got 29 mpg—even better

Partly because it’s a V-6 rather than a V-8, the EcoDiesel is priced at just $2,850 over the 5.7 Hemi gasoline engine. That’ll be hard to resist by anyone who puts on a lot of miles working or playing with his Ram 1500 pickup.

6.4 Hemi V-8

Ram Heavy Duty pickup and chassis-cab trucks have the capable 5.7-liter Hemi V-8 and the burly 6.7-liter I-6 Cummins Turbo Diesel, and now they have the 6.4-liter, 391-cubic-inch Hemi that fits in between. This should be right for customers who have serious hauling jobs but want to stay with less expensive gasoline power. The new engine has big output—410 horsepower and 429 lb.-ft.—and while it will use more fuel than the Cummins diesel, it’ll cost about $6,500 less to buy.

The 6.4 Hemi also raises payload and towing numbers and has diesel-like features, such as dual alternators, left- or right-side PTOs, and timed idle shutdown. Cylinder shutdown occurs under light loads in drive and PTO modes. The 6.4 will cost $1,495 more than the Hemi 5.7, which will still be standard in lighter HD pickups up to the single-rear wheel Ram 3500, while the 6.4 will be standard in duallies.

This is not a converted Dodge SRT auto engine, execs at the event insisted, but a truck engine all the way through. Computer simulations and exhaustive testing indicate it will perform reliably for at least 200,000 miles. (The Cummins diesel’s minimum life is 250,000 miles, but it goes much longer because it’s basically an ISB commercial engine.) 

Among the 6.4 Hemi’s features are cooled exhaust-gas circulation; an active two-path air intake, with the second one opening when sensors tell engine controls that more cooling is needed; and dual-runner-length intake manifolds. It has hardened valves and valve seats, so propane and natural gas fuels might be authorized in the future.

Driving it in a Ram pickup was both impressive and surprising. The engine’s definitely got the go-power of a “big honkin’ motor,” though it had to rev to make it happen. The truck was a single-rear-wheel Ram 2500 with a very roomy four-door crew cab with a sumptuous Laramie interior –almost too nice to work but capable of a lot of it: Payload is more than 5,000 pounds.  It had a five-link, coil-spring rear suspension, so rode rather well.

The Chrysler 66RFE 6-speed automatic (also used with the 5.7 Hemi) was controlled by a column-mounted shifter with an up- and down-shift slide switch near the end of the lever. On the downgrades I used it a lot to help control our velocity, but left it alone on the level.

The engine made a nice deep exhaust note, but much of the sound seemed to come from mechanical sources and combined to make it seem rather busy.  Modest calls for power were answered with an immediate rise in revs from 1,600 or so with no pedal to 2,000 and above. A serious stomp saw revs climb fast to 3,000 and 4,000 rpm as the tranny stayed in lower gears until desired road speed was reached, all accompanied by a roar from under the hood.

I thought an engine this big ought to loaf more and let torque rather than horsepower do the propulsion job.  Then again, Ford’s gasoline V-10 also wants to rev when the go-pedal is pushed. I guess I’ve driven too many low-speed diesels and want the gasoline engines to behave the same way. Still, the propulsion is there, and it will be useful for many serious truck operators.

Promaster van

Another serious truck is the new Promaster full-size Euro-style van, which Ram execs also showed off at the California event. We’re not making much of it here because walk-in vans are seldom seen at construction sites. But you might be interested to know that with the standard 3.6-liter Pentastar gasoline V-6, this roomy creature scoots almost as well as those pickups, at least while pulling away from traffic stops. It has front-wheel drive that allows the unibody’s cargo floor to sit low for easy loading. The vans are arriving at Dodge Ram dealers, and are worth a look.