Parts / DEF Pump
Used DEF Pump for Medium-Duty Trucks
DEF pumps / supply modules — clear the derate countdown and get the truck back to full power.
- Used OEM part
- Tested before shipping
- 30-day warranty
- Ships to the lower 48
A DEF pressure code on a 2010-and-newer diesel starts a clock: warning, then a speed derate, then 5 mph. The DEF pump (supply module) is the most common cause of low-pressure codes like P20E8, and the new part from the dealer — when it’s in stock — costs more than most fleets budget for an emissions component.
We supply used OEM DEF pumps from running donor trucks, tested for pressure build and covered by our warranty, matched to your engine and model year so the connector, lines and calibration line up. We’ll help you read the codes before you order.
Signs your def pump has failed
- DEF/SCR warning lamp with a derate countdown, or a speed limit already active
- P20E8 (reductant pressure too low), P204F or P208A (reductant system performance / pump control)
- DEF pump won’t prime — no hum at key-on
- Crystallized DEF at the pump, filter or lines
- DEF pressure builds, then collapses
- Repeated failed DEF quality or regen cycles after a refill
Before you order
- Send your VIN and engine — DEF supply modules are engine- and year-specific, and Isuzu, Ford, GM, Ram and Fuso each use different units.
- Check the DEF filter (where serviceable), the lines for crystallization, and the pump’s power and ground before condemning it.
- Use fresh ISO 22241 DEF from a sealed container after replacement — old or contaminated DEF is what killed the original.
- A scan-tool reset/relearn of the SCR system is typically required after the swap; the derate clears once the system passes its self-test.
Select your truck for a def pump quote
Chevrolet
Mitsubishi Fuso
Related parts
Frequently asked questions
Which trucks do you stock a used DEF Pump for?
Isuzu NPR, NQR and NRR; Ford F-450 and F-550; Chevrolet Silverado and GMC Sierra 4500HD/5500HD plus Kodiak and TopKick C4500; Ram 4500 and 5500; and Mitsubishi Fuso Canter FE125–FE180. Pick your truck below or send us your VIN.
Is a used DEF Pump tested before it ships?
Yes. Every def pump we sell is pulled from a running donor truck, inspected and tested before it ships.
How do I get a quote for a used DEF Pump?
Use the form on this page or call us. Share your truck and VIN and we confirm exact fitment, then call you back with a price in about 30 seconds during business hours — or email it if we can’t reach you.
Is a used DEF Pump covered by a warranty?
Yes, we stand behind this def pump with our warranty. Exact terms are confirmed on your quote.
Do you ship a used DEF Pump nationwide?
Yes — we ship to all 48 contiguous states with tracked delivery. Most parts arrive in 3–7 business days; engines, transmissions and axles ship freight and typically arrive in 5–10.
Will a used DEF pump clear the derate?
If the fault is the pump, yes — after installation and the SCR system reset, the truck runs its self-check and the countdown clears. If the code is a NOx sensor, DEF injector or quality sensor, it won’t; our DEF guide narrows it down.
Are used DEF pumps tested?
Every DEF pump is checked for pressure build before it ships.