Freightliner Century 112/120 DPF & Mufflers

Frequently Asked Questions About Freightliner Century 112/120 DPF & Mufflers

Will this DPF or muffler fit my Freightliner Century 112 or 120?

Fitment depends on your truck's model year, engine type, and exhaust configuration, since the Century 112 and 120 were built with several different engine options over their production run. Always check the listed specifications, part numbers, and OEM cross-reference information on each product page, and compare them to your truck's existing unit or engine tag before ordering. If you're unsure, our team can help you verify compatibility using your VIN or engine serial number.

Should I buy a new, used, or reconditioned DPF?

Each option has its place depending on your budget and how quickly you need the truck back on the road. New units offer the longest expected service life, used parts are budget-friendly options for older trucks, and reconditioned or remanufactured DPFs have typically been cleaned, tested, and inspected to restore proper function at a lower cost than new. Consider your truck's mileage, how long you plan to keep it, and your maintenance history when deciding which option makes sense.

How do I know if my DPF needs cleaning versus replacement?

Common signs of a failing or clogged DPF include reduced engine power, frequent regeneration cycles, dashboard warning lights, or increased backpressure readings. In many cases, a clogged filter can be professionally cleaned and returned to service, but excessive soot loading, physical damage, or repeated failures usually point to the need for replacement. A shop with proper diagnostic equipment can test backpressure and confirm whether cleaning or replacement is the right call.

What's involved in installing a replacement muffler or DPF?

Installation generally involves removing the old unit from its mounting brackets and exhaust piping, then installing the replacement using the same hardware and gaskets, or new ones if the originals are worn or damaged. Because these components are heavy, positioned underneath the truck, and connected to exhaust piping that must seal properly, most customers have this work done by a qualified diesel technician rather than attempting it in a home garage.

Are these parts compliant with emissions regulations?

DPFs are emissions-related components regulated by the EPA, so any replacement unit should match your truck's original emissions configuration to remain compliant. Used and reconditioned DPFs sold through us are pulled from take-off trucks or processed as functioning emissions parts, not aftermarket deletes, but you should always confirm the specific part matches your engine's certified emissions setup before installing it.