MAINTENANCE
6-26 / Engine, Cooling, Fuel and Exhaust
© 2020 Pierce Manufacturing Inc. All Rights Reserved.
6-20.1 General Notes for All 2010 EPA & 2013 EPA Engines
No modification of the exhaust between the engine, Diesel Particulate Filter (DPF), and Selective Catalytic
Reduction (SCR) is allowed per the EPA. Only tailpipes after the SCR are allowed to be changed.
6-20.2 Exhaust Diffusers
NOTE: All 2010 EPA & 2013 EPA engines with Diesel Particulate Filters (DPFs) are equipped with exhaust
diffusers. Some Cummins ISM engines, 450 HP and higher, do not have DPFs.
Pierce Custom Chassis may be outfitted with diffuser exhaust tips. These devices lower exhaust gas temperatures
as they exit the tailpipe. Exhaust Diffusers reduce exhaust outlet temperature by mixing ambient air with engine
exhaust. If equipped, the Exhaust Diffuser installed on your truck should not be removed or modified in any way and
must be replaced if damaged or missing. Consult your Pierce Dealer for exhaust extraction systems that are
compatible with the Pierce diffuser tips.
Building exhaust extractor systems used with 2010 EPA & 2013 EPA DPF equipped engines must be designed and
installed to accommodate the larger diameter pipe, accept higher exhaust flow rates and higher exhaust
temperatures present with these engines.
All customer installed hardware needs to be kept a minimum of 6 inches away from any exhaust pipe
and After Treatment Device (ATD) housing. Failure to comply may result in heat related damage to the
aftermarket components.
Performance of the Exhaust Diffuser can be adversely affected by:
• Exhaust Diffuser ambient air inlet obstructions.
• Exhaust Diffuser outlet obstructions.
• Damage to the Exhaust Diffuser.
• Inadequate building exhaust extractor system flow capacity.
Reduced Exhaust Diffuser function can result in exhaust temperatures approaching 1200°F (649°C) at
the outlet during or shortly after Diesel Particulate Filter (DPF) regeneration.
DPF regeneration can take place and high exhaust temperatures can be present while operating the
truck in a stationary pumping mode.
To Next Page
Loading...
