Drive: 2003 Dodge Ram Heavy Duty
© PickupTruck.com, 2002Posted:
rolled out the all-new Ram light-duty trucks last year, those vehicles
were saddled with the company's 4.7-liter overhead cam and 5.9-liter overhead
valve engines. Truck enthusiasts have had to wait until the introduction
of the 2003 Dodge Ram Heavy Duty models to get their first glimpse of
the long-rumored 5.7-liter Hemi engine. It has been worth the wait.
the Hemi looks like a winner, and the good news is that it delivers on
that promise. The twin spark plug design lets the engine idle as low as
500 RPM when stopped with the transmission in drive. This condition causes
the old engines to sputter and shake, but it remains difficult to tell
the Hemi is even running.
brake and floor the accelerator and the good news continues. The 345 peak
horsepower and 375 lb.-ft. peak torque sound good, but just as importantly,
the low-end torque curve never dips below that of the old 5.9-liter engine.
That makes launches easy even while towing heavy trailers. Back-to-back
drives with the 6.0-liter Chevrolet Silverado showed that the Hemi matches
the Chevy in seat-of-the-pants power and smoothness.
hushed the Hemi's mechanical clatter and intake honk, leaving more decibels
available for the exhaust. The result is a pleasing rumble that enthusiasts
will love, but that is quiet enough that passers-by won't notice if they
don't want to.
still no announcements regarding wider use of the Hemi engine, but Dodge
officials confirmed that the new engine plant's capacity won't be taxed
by the 25 percent of Ram Heavy Duty trucks powered by gas engines. The
8.0-liter V-10 gas engine is carried over as the maximum-power gas engine
available in the Ram.
us to the new 5.9-liter, 305-horsepower, 555 lb.-ft. Cummins turbodiesel
that motivates 75 percent of heavy-duty Ram trucks. The new high output
engine manages impressive power that permits a 23,000 pound GCWR (that
is truck, trailer and cargo) towing capacity. We tested the Cummins matched
with the new six-speed manual transmission while pulling a flatbed gooseneck
trailer loaded with a Ford extended cab heavy-duty truck, and found acceleration
to be excellent.
gearbox shifts easily, and getting the truck and trailer underway smoothly
required no special effort or clutch-slipping, despite the heavy trailer.
The new Cummins engine is significantly quieter, slashing 8 decibels (that's
an 80 percent reduction in sound pressure) from the old engine's racket
at idle, and running 6 db quieter at highway speed. The engine's diesel
sound and character remain intact, but that character is no longer intrusive.
will appreciate the 15,000-mile oil change interval, doubled from the
previous 7,500 miles. The oil that comes out should be significantly less
foul, because Cummins has reduced the particulate blow-by that turns oil
inky black. A 250-horsepower, 460 lb.-ft. version of the engine is also
available, for drivers who don't need the extra towing capacity of the
trucks look the same as the light-duty versions, but for the bigger standard
17-inch wheels and tires. The two-wheel-drive models feature rack and
pinion steering - a first among heavy-duty models -- while the four-bys
have a new low-friction steering box for their recirculating ball steering
that gives better on-center feel and feedback than the old truck's steering.
frame is fully boxed, front to rear, for maximum rigidity, and is hydro-formed
of thicker steel than the light-duty trucks. The two-wheel-drive trucks
receive a new independent front suspension, and the four-wheel-drive model,
which accounts for 70 percent of heavy-duty Ram sales, has a new front
axle. Standard rear axle ratio is 3.73, and a 4.10 is available optionally.
Rear leaf springs are three inches longer for a more compliant ride.