Don’t let the CP4 fuel pump destroy your engine, Unlimited Diesel Performance is here to help.
TL;DR: Ford’s 6.7L Powerstroke CP4 fuel pumps are notorious for sudden, catastrophic failures that can leave drivers with five-figure repair bills. In Bremen, OH, more diesel owners are upgrading to the S&S Diesel DCR Conversion Kit at Unlimited Diesel Performance in 2025 to protect their trucks, improve reliability, and avoid costly downtime.
Protect Your Engine from CP4 Failure with S&S Diesel Solutions
If you own a Ford Super Duty with the 6.7L Powerstroke engine, there’s a high chance you’ve heard the horror stories about CP4 pump failure. These stories aren’t exaggerations. They’re warnings.
At Unlimited Diesel Performance in Bremen, OH, we’ve seen firsthand what happens when these fuel pumps fail. We’ve also seen the relief and satisfaction on our customers’ faces when they upgrade to the S&S Diesel DCR Conversion Kit, a true fix for one of the most notorious problems in the diesel world.
Let’s dig into why diesel drivers in Ohio (and far beyond) are upgrading their fuel systems in 2025 and how you can protect your Powerstroke before it’s too late.
Understanding the Problem: CP4 Pump Failure in 6.7 Powerstroke Trucks
Starting in 2011, Ford equipped their 6.7L Powerstroke diesel engines with a high-pressure fuel injection pump known as the CP4. On paper, it seemed like a good fit. In practice, it’s proven to be one of the most failure-prone components on the truck.
Here’s what’s happening:
The CP4 uses a two-lobe cam design with metal-to-metal contact and relies solely on fuel for lubrication.
Over time—or sometimes without any warning—the internal roller can rotate 90 degrees, grinding into the camshaft.
This sends tiny, hardened metal particles throughout the fuel system, damaging injectors, fuel rails, and in many cases, the engine itself.
In the worst scenarios, the pump locks up, creating enough force to spin the unkeyed crankshaft gear. That throws the engine out of time, often causing catastrophic valve and piston contact.
Some failures are also caused by contaminated fuel, often from water or debris picked up at the pump. Others are the result of user error, like accidentally filling the fuel tank with Diesel Exhaust Fluid (DEF). It’s more common than you’d think, especially with how close the filler necks are on these trucks.
The result? A five-figure repair bill. If you’re out of warranty, you’re footing the whole thing.
Real Talk from the Shop Floor: What We See at Unlimited Diesel
We’re not just talking theory here. This is what we deal with weekly.
Sometimes, there are no warning signs. Trucks come in on a tow truck, completely shut down. Other times, there are hints: long crank times, crank-no-start issues, or codes like P0087 (fuel rail pressure low). Regardless of how it presents, once a CP4 pump fails, you’re likely looking at:
- Full fuel system replacement
- New injectors and fuel rails
- Fuel tank draining and flushing
- Potential engine replacement
Even a “mild” failure means thousands of dollars in parts and labor.
We always start with a fuel sample from the separator to check for contamination. But once metal is in the system, there’s no halfway fix. You either rebuild it all or prevent the issue entirely.
“We can’t keep the conversion kits on the shelf,” said Unlimited Diesel Performance owner Nate Bailor.
That alone should tell you how seriously diesel truck owners are taking the CP4 problem—and how many are choosing to prevent failure before it happens.
The Permanent Fix: S&S Diesel DCR Conversion Kit
The DCR Conversion Kit from S&S Diesel is hands-down the best solution to eliminate CP4 pump failures. And we’re proud to be a Premium Dealer and Direct Distributor for these kits right here in Ohio.
Proven Reliability
The DCR pump is built on a globally trusted foundation. Its core design has been used in over a million commercial and industrial diesel engines worldwide, especially in Europe, India, and China. Originally developed by Stanadyne for high-stress environments, this base pump architecture has seen extensive real-world use long before being adapted to Ford’s Powerstroke platform.
The DCR pump was brought to life for North American applications through a powerful collaboration between Stanadyne, PurePower Technologies, and S&S Diesel. PurePower Technologies, a Stanadyne company, played a key role in the design and engineering of the DCR pump, bringing their extensive experience in fuel system manufacturing to the table.
Today, these pumps are manufactured at PurePower’s state-of-the-art facility in South Carolina, ensuring exceptional quality control and modern production standards. The result is a fuel pump with the kind of real-world reliability and pedigree that the CP4 never had.
At Unlimited Diesel Performance, we’re not just fans of the S&S DCR Conversion. We’re a Premium Dealer and direct distributor for S&S Diesel. That means we have trusted access to the product line, install them regularly, and stand behind their performance.
Built-In Durability
Durability is where the DCR truly outshines the CP4. The CP4’s two-lobe cam design relies on metal-to-metal roller contact that is only lubricated by diesel fuel. This leaves it vulnerable to wear, roller rotation, and eventual catastrophic failure, especially with today’s low-lubricity Ultra Low Sulfur Diesel.
In contrast, the DCR pump features:
- An eccentric offset cam drive
- A large bushing-supported roller assembly
- Pressure-lubrication through the camshaft, similar to how crankshafts oil their main bearings
This design drastically reduces friction, eliminates the common points of failure, and is engineered for long life even under harsh conditions. It’s not just more robust, it’s built to last.
No Tuning Required
While many aftermarket upgrades require tuning or ECU modification, the DCR Conversion Kit is a true drop-in solution. It was designed to:
- Integrate seamlessly with OEM fuel system electronics
- Use factory quick-connect fittings and mounting locations
- Retain full compatibility with stock fuel maps
That means no tuning, no custom programming, and no warranty complications. Just install it and go with immediate performance and reliability gains.
This was made possible by the innovative engineering of S&S Diesel, Stanadyne, and PurePower Technologies—a Stanadyne company—who together developed a proprietary integrated metering valve and control system that mimics CP4 functionality while delivering superior performance.
OE Fit, Better-Than-OE Finish
When it comes to installation, the DCR kit fits like it was made for the truck because it was.
Each kit includes:
- A precision-machined DCR pump
- Custom front flange and backplate
- High-quality IMV (inlet metering valve)
- Compatible hardware for 2011–2025 Ford 6.7L Powerstroke engines
It’s not just about performance. It’s about fit, finish, and function. Everything bolts in without modification and performs better than the part it replaces. The result is a clean, OE-level installation with upgraded durability and zero compromise.
When Budget Is Tight: CP4 Disaster Prevention Kit
We get it. Not everyone can spring for a full DCR conversion right away. That’s where the CP4 Disaster Prevention Kit comes in.
This kit doesn’t stop the pump from failing, but it does one important job: traps metal debris in a 9-micron filter and returns it to the tank instead of sending it through the rest of the fuel system.
It’s saved plenty of trucks from complete failure.
- Cost-effective: around $400 for the kit (parts only)
- Protects injectors and fuel rails
- Good short-term insurance if you’re not ready to convert yet
Still, we always remind customers that the only way to truly eliminate the CP4 issue truly is to remove the CP4 pump entirely.
A Behind-the-Scenes Origin Story: How the DCR Pump Was Born
One of the most compelling parts of the DCR story is how it came to be.
Ryan Reiser, a former development engineer for Stanadyne (and now part of the S&S team), had a personal wake-up call. On his very first pass down the drag strip in his 6.7L race truck, the engine died. It turns out that his CP4 pump had seized, locking up the engine and destroying the entire fuel system.
That failure led Ryan to research more durable pump options. He found a heavy-duty pump design already in use overseas. With a few engineering tweaks, the S&S team transformed it into the DCR pump we install today.
It’s not just a product. It’s the result of real-world frustration, innovation, and a passion for doing things better.
Additives and Maintenance: Supporting Long-Term Diesel Fuel System Health
Even with a solid pump, your fuel system needs support.
Modern Ultra Low Sulfur Diesel (ULSD) has just 15 parts per million of sulfur. That means far less lubricity than older diesel fuel formulations. That lack of natural lubricant is one of the big reasons CP4s wear out fast.
We recommend:
- Alliant Power UltraGuard
- Hot Shot’s Secret EDT Fuel Additive
Paired with 15,000-mile fuel filter changes, these additives help reduce wear, improve injector longevity, and protect your investment, whether you’re running a CP4 or a DCR.
Our Process: What to Expect When You Upgrade at Unlimited Diesel
- Consultation – We walk you through your options: DCR conversion, disaster prevention kit, or full fuel system overhaul.
- Diagnosis – If you’re unsure of the current state of your fuel system, we’ll pull samples and inspect them thoroughly.
- Installation – Our trained techs handle the conversion with precision. We use Snap-On diagnostics, digital vehicle inspections, and provide complete transparency through photos, videos, and service notes.
- Follow-Up – Every customer gets post-service communication. If anything is less than 100 percent, we’ll make it right.
We don’t just work on diesels. We drive them, build them, and push them to perform.
Frequently Asked Questions About 6.7 Powerstroke CP4 Pump Failure
What is the S&S Diesel DCR Conversion Kit?
The DCR Conversion Kit is a drop-in replacement for Ford’s CP4 pump. Engineered by S&S Diesel, Stanadyne, and PurePower Technologies—a Stanadyne company—it features a more durable cam, a pressure-lubricated roller design, and OEM-level integration. No tuning is required, and it eliminates the CP4’s main failure points.
Why does the CP4 pump fail in Ford 6.7 Powerstroke trucks?
The CP4 pump fails due to its two-lobe cam design, metal-on-metal contact, and reliance on diesel fuel for lubrication. When parts wear or seize, metal shavings circulate through the entire system, often destroying injectors, rails, and even engines.
Is the CP4 failure covered under warranty for Ford trucks?
Even when the vehicle is under warranty, Ford typically denies claims of the CP4 failure, and it is normally blamed on contamination. We are not aware of situations where this has been successfully claimed under warranty at any of our local dealers.
How do I prevent CP4 pump failure in my Powerstroke?
The best way to prevent CP4 pump failure is to replace it with the S&S Diesel DCR Conversion Kit. You can also use a CP4 disaster prevention kit and high-quality diesel fuel additives to improve lubrication and reduce wear.
Is a Disaster Prevention Kit enough protection for my CP4?
A Disaster Prevention Kit helps trap metal shavings if the CP4 fails, protecting injectors and rails. However, it doesn’t prevent pump failure. For complete peace of mind and long-term reliability, most owners upgrade to the S&S DCR Conversion Kit.
How often should diesel drivers service their fuel system?
Most experts recommend fuel filter changes every 15,000 miles and regular use of lubricity additives with modern ULSD fuel. Annual inspections help detect contamination or wear early. Proactive care extends the life of injectors, pumps, and overall diesel performance.
Key Takeaway:
CP4 pump failures aren’t a matter of if but when—and when they happen, the damage is extensive. Bremen diesel drivers are turning to Unlimited Diesel Performance for proactive solutions like the S&S DCR Conversion Kit, Disaster Prevention Kits, and professional maintenance. The bottom line: an upgrade today saves thousands tomorrow and ensures long-term Powerstroke reliability.
Diesel Fuel System Upgrades in Bremen, OH - Schedule now!
Don’t let the CP4 fuel pump destroy your engine. Whether you want the peace of mind of a DCR Conversion, the budget-friendliness of a Disaster Prevention Kit, or just real advice from people who know diesel, Unlimited Diesel Performance is here to help.
We serve diesel truck owners from Lancaster to Columbus, and we’re proud to be a trusted name across Ohio, West Virginia, Kentucky, and beyond.
Call us today at 740-569-1319 or visit us at 408 Logan-Thornville Rd NE, Bremen, OH, or learn more at www.unlimiteddiesel.com
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