kirks emissions parts

Fleet & Transit Emissions Replacement Parts

KIRKS is proud to be the leading provider of transit emissions and fleet emissions replacement parts. We’ve been assisting transit and fleet maintenance teams since 1946, and have everything you need to pass EPA requirements. Our inventory of transit and fleet emissions parts ranges from filters to dosing modules.

Keep reading to learn more about what we carry, or call your KIRKS product specialist today to request a quote.


Filters are perhaps the most common type of fleet emissions part. At KIRKS, we carry diesel oxidation catalysts, diesel particulate filters, and selective catalytic reduction filters manufactured by RoadWarrior.

DOC: Diesel Oxidation Catalysts

Diesel oxidation catalysts (DOC) are designed for use in heavy-duty trucks. They are an essential part of the after-treatment emissions system. It is important to change DOCs regularly to prolong engine life.

DPF: Diesel Particulate Filter

A diesel particulate filter removes soot from a heavy truck’s after-treatment system, which reduces pollution. DPFs are essential for meeting emissions regulations.

SCR: Selective Catalytic Reduction

The selective catalytic reduction part is another essential component of an after-treatment system. This part can also help maximize fuel economy.

Supply Modules

In addition to our wide range of emissions filters, we also carry BOSCH® supply modules. The supply module transports diesel exhaust fluid (DEF)/AdBlue® from the vehicle’s tank to the dosing module. Supply modules also help to ensure that your fleet fulfills emissions requirements. 

Dosing Modules

KIRKS carries many certified aftermarket dosing modules from BOSCH® Dosing modules are responsible for reducing nitrogen oxide in exhaust systems. Modules do this by spraying a urea solution (DEF) into the exhaust system. 


We also offer transit and fleet emissions NOX and temperature sensors. These sensors are vital for several reasons. First, they make sure that every component of your emissions system is functioning properly. These sensors can also let you know when your vehicle isn’t meeting applicable emissions requirements. These sensors must be replaced regularly, as their accuracy deteriorates over time. If you’re not sure whether or not you need a new emissions sensor, contact your KIRKS product specialist today.