9
Q. Do trucks equipped with scr have a Diesel particulate filter (Dpf)?
a.
Yes they do. The DPF serves a different function than the SCR; it helps
remove soot from the exhaust. For 2011, the range between Duramax
DPF regeneration cycles has been lengthened by 75% and is now up to
700-miles. This improves fuel economy performance since less diesel fuel
is required to clean the DPF. (Based on GM testing.)
Q. will Def freeze?
a.
Yes, DEF will freeze—at approximately 12ºF. If DEF is frozen, the vehicle
will start as it always has. After the engine is started, the DEF tank and
lines are electrically heated to ensure adequate DEF delivery in cold
weather. The DEF thaws with no degradation. Remember, since this
system was designed to operate in cold weather, there is no impact on
cold-weather engine operation.
Q. Does Def expand when it freezes and if so, how does it impact the tank?
a.
Yes, DEF expands when it freezes. The vehicle’s DEF tank and all DEF
packaging is designed to accommodate any expansion that may result
from being frozen.
Q. can a freeze-point improver be added to the Def to keep it
from freezing?
a.
No, doing so would alter the DEF mixture balance potentially triggering
an “EXHAUST FLUID QUALITY POOR” DIC message.
Q. what effect does high-temperature driving have on the vehicle?
a.
High ambient temperatures do not affect the operation of the vehicle.
Q. is Def flammable?
a:
No.
