AQUEOUS CLEANING DPF, DOC, SCR
An Innovative Method to Clean DOC, DPF & SCR — Plus EGR Cooler Cleaning
Our Active Filter Pro™ aqueous cleaning system is the ultimate solution for restoring your diesel emissions components. This specially formulated method gently but thoroughly cleans DPF, DOC and SCR filters of all sizes and shapes without damaging the substrate. With adapters for tapered inlets and outlets, we soak, loosen and flush out soot and ash and bring flow back — all without the long bake cycle of older methods.
The 4 Emissions Components We Clean
Modern diesel aftertreatment runs in a set order — Engine → DOC → DPF → DEF injection & mixer → SCR → tailpipe. Here’s what each part does, and how our Active Filter Pro™ system cleans the three aftertreatment substrates.
DOC — Diesel Oxidation Catalyst
First stage after the engine. The DOC catalyst converts carbon monoxide and unburned hydrocarbons into CO2 and water vapor. Over time the substrate loads up and chokes flow — we restore it in our Active Filter Pro™ aqueous system. Note: on a One Box, the DOC is built in and can't be removed for cleaning.
DPF — Diesel Particulate Filter
Second stage, ahead of the DEF injection point and SCR. This wall-flow filter uses alternating plugged channels to trap 85-100% of soot particulate. Soot has to be regenerated to ash, and neglected ash plus moisture can sinter into a cement-like blockage. Our aqueous clean gently loosens and flushes soot and ash from the substrate. The DPF is the removable, cleanable core — and the only removable part on a One Box.
SCR — Selective Catalytic Reduction
The final catalyst, just before the tailpipe. DEF (urea-based diesel exhaust fluid) is injected upstream and reacts over the SCR to cut NOx. DEF-dosing faults can crystallize inside it — we clear that buildup by cleaning the SCR substrate in our aqueous system. Note: on a One Box, the SCR is built in and can't be removed for cleaning.
EGR — Exhaust Gas Recirculation
Grouped with the other three, but technically an engine-side control: it recirculates a portion of exhaust back into the intake to lower combustion temperatures and cut NOx at the source. Because it lives at the engine — not in the DOC/DPF/SCR aftertreatment line — it sits outside what our Active Filter Pro™ aqueous system cleans. We list it here so you know exactly where it fits in the system.
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after
AQUEOUS CLEANING Advantages
- Quick turnaround, premium 2-hour service available for emergency truck down situations.
- Non-Destructive, ensuring that the filter particulates remain intact.
- OEM performance, the process cleans to perform within OEM specifications.
- Continuous low-pressure / high-volume water stream allows water to navigate around the cell wall structures.
- DPF/DOC filter substrates have special coatings which is what enables them to capture pollutants in your exhaust that can be damaged in the baking cleaning process which can decrease the life span of your filters. Our Active Filter Pro™ does not bake or super heat your filters so it will not affect these coatings in any way extending the life of your substrates.
- Our aqueous cleaning process floods the entire substrate evenly ensuring all parts of the substrate are cleaned thoroughly at once automatically removing deposits and highly clogged areas that decrease differential pressure across the entire surface of the substrate allowing your engine to breathe easily again.
- Our Active Filter Pro™ is equipped with a 3-stage filter system that removes contaminants down to 1 micron.
- The Active Filter Pro™ is the only cleaning machine with true dual cleaning heads, meaning we can clean a complete filter set, DPF and DOC at the same time without ANY loss in cleaning efficiency or decrease in flow, getting your complete set cleaned and back on your engine faster and cleaner than any other Aqueous cleaning process on the market today.
- Our machine's cleaning power is programmed with various cleaning procedures making it gentle enough to clean individual filters from the smallest compact engines and strong enough to clean an entire one box such as a Freightliner/Detroit Cascadia, Volvo/Mack, G.M./Isuzu, and many more.
- Every cleaning comes with a complete worksheet filled out by the technician that cleaned your equipment, giving you differential pressure flow rates telling you exactly what air flow you had before and after our cleaning.
Cleaning Capabilities
Our aqueous cleaning skips the long baking cycle of older methods — we soak each filter in a specially formulated surfactant solution to loosen and flush out the soot, ash and buildup inside.
Cleaning Methods
Active Filter Pro™ Aqueous Cleaning
Our flagship, in-depth clean for DPF, DOC and SCR substrates. The Active Filter Pro™ cabinet soaks each filter in a specially formulated surfactant-and-water solution that gently loosens and flushes out soot, ash and debris — no substrate damage, and none of the long bake cycle older methods rely on. Adapters fit tapered inlets and outlets and filters of every size and shape.
Thermal Regeneration (Oven Baking)
For oil-soaked, oil-contaminated units that plain regeneration can't clear, we bake them out in a controlled oven cycle to lift what water alone won't.
Pneumatic Cleaning (Bake & Blow)
Compressed-air cleaning that dislodges and blows out loosened ash — the finishing step after an aqueous or thermal clean.
One Box Aftertreatment
We service single-module One Box units. On these, the DOC and SCR are built in and can't be removed, so only the DPF comes out for cleaning. We handle it right and tell you straight what can and can't be done.
Repairs & Parts
Restore for Backordered or Discontinued Filters
When a replacement simply can't be sourced, our Restore process rebuilds your existing filter so a backordered or discontinued unit doesn't sideline the truck.
New Filters, Clamps & Gaskets
We stock new filters, clamps and gaskets for popular truck models — so when a clean isn't enough, the replacement is on hand.
DOC Muffler Stack Repair
We repair DOC muffler stacks to bring damaged assemblies back into service instead of replacing the whole unit.
Combustor Canister Repair
We repair combustor canisters, restoring the housing and getting your aftertreatment back to working order.
What Our Emissions Customers Say
★★★★★
A $6,000 dealer quote — cleaned for a third of the price
I can’t say enough good things about Active Radiator in Lakeland, FL! My Dodge Ram 3500 was constantly tripping exhaust system codes, and the dealership quoted me nearly $6,000 for DPF and DOC filter replacements plus bung repairs. I removed my exhaust stack and brought it in — their team used their water machine to flush out my entire system in just one day, and it cost me only a third of what the dealer wanted for new filters. It’s been over 40,000 miles since the cleaning and my truck is still running perfectly, with no codes triggered. These guys saved me thousands of dollars and a ton of headaches. Highly recommend!
— Joe, Tampa, FL
★★★★★
Outstanding service and savings on a DPF restore
As the owner of a diesel repair shop in Lincoln Park, NJ, I handle diesel emissions cleaning daily. We had a customer with a Cummins B6.7 in a Peterbilt 536 food delivery truck that needed a DPF cleaned, and after cleaning we found the substrate was damaged. Active Radiator went above and beyond — they restored the DPF by putting a brand-new substrate into the original can. That saved my customer a significant amount versus replacing the whole DPF and minimized downtime, which is critical for a food delivery operation. They’re now my go-to for DPF restoration. Professional, top-notch work!
— Diesel Repair Shop Owner, Lincoln Park, NJ
★★★★★
Saved my small business a ton of money
I run a small food truck business in the Chicago area, and my Isuzu 4500XD is the backbone of my operation. Since it idles constantly, I ran into emissions system issues, and the dealer told me my emissions box wasn’t cleanable and I’d have to buy a brand-new one. I took it to Joe and his team at Active Radiator’s Joliet, IL location and they went above and beyond — they cleaned all the filters in the emissions box for less than $1,500, saving me a ton compared to a new unit. Their expertise, affordability, and commitment to customer service are unmatched. You’ve earned a customer for life!
— Food Truck Owner, Chicago, IL
Ready to Get Your Filter Cleaned?
Call our team or find your nearest location.
Frequently Asked Questions
Active Filter Pro™ Locations — Click to Call
Drop your DPF, DOC, SCR or One Box at any location below. 3 Active Filter Pro™ centers do the cleaning on site; our drop-off locations send your unit to the nearest one.
New Active Filter Pro™ Locations Coming Soon