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Ceramic glow plugs signifcantly
reduce the time it takes for the
cylinders to reach temperature,
and run at higher temperatures
with increased longevity.
The 2.8-liter Duramax uses a multi-
step emissions control system that
begins with cooled EGR to lower
combustion temperatures (and NOx
emissions) by redirecting some of
the exhaust gasses back into the
intake manifold. Next up is an
engine-mounted oxidation catalyst
that reduces hydrocarbon forma-
tion, followed by an SCR system
that adds urea to the exhaust gas
stream before it is adsorbed onto a
catalyst. The urea tank holds fve
gallons, and is topped of during
the normal 7,500 mile service.
Should it be necessary to fll the
tank before the next service, the
fller cap is located next to the
fuel fller, and a warning light will
illuminate 1,000 miles before a soft
shut down is initiated. In addition,
the engine has a diesel particulate
flter with a dedicated diesel fuel
injector. According to Yackley,
"This allows us to follow
an aggressive regeneration
schedule without a reduction
in engine power whether the
vehicle is out on the road or
idling through a 'farm cycle'
in the felds."
t This 2.8-liter inline four has
181 hp and a mighty 369 lb.-ft. of
torque to go with its comprehensive
emission control strategy. The turbo-
diesel uses one single-scroll variable-
nozzle Honeywell turbo pumping out
35-40 lb./in.
2
of boost.