How to Make a 6.4 Powerstroke Reliable-Ultimate guide

6.4L Powerstroke was an upgrade from the faulty 6.0L diesel engine, particularly for reliability.

The International engine was still plagued by bugs carried over to the 6.0L. Despite that, the 6.4L became a favorite engine thanks to its power increases.

It is possible to make the 6.4L Powerstroke more reliable by replacing the radiator, pistons, and EGR coolers using durable aftermarket alternatives. You can also replace the engine oil at regular intervals and add a cooling system with filtration.

This article will show you how to make a 6.4L solid. Certain tips involve replacing components, while others will require the installation of extra ones.

Replace the stock Radiator.

The radiator will likely be the first component that fails in the 6.4L Powerstroke. Cracks develop on the edges of the radiator tanks made of plastic due to their low quality and the huge engine vibrations. In the process, coolant leaks through the cracks.

If you spot the dripping of coolant underneath your vehicle, the most likely culprit is the radiator that came with it. Other signs of leaky coolant are excessive heat and steam coming from the engine.

The only option is changing the stock radiator with an aluminum aftermarket. You can also install an extension bar for the radiator to increase the rigidity and stop the unit from flexing caused by engine vibrations.

For tractors, I recommend the CoolingCare All Aluminum Aftermarket Tractor Radiator for New Holland/Ford (available at

It will not only boost your vehicle’s cooling to 30 percent more efficiently, but also, despite its status as an aftermarket item, the unit has been thoroughly examined to identify any issues that could cause your radiator to not run smoothly.

Replace the Pistons

The pistons in the 6.4L Powerstroke had a major problem: the design of the pistons meant that they were prone to cracking.

International-produced pistons with the sharpest lip but a tiny material on top. Ultimately, the piston breaks and the engine cannot properly ignite.

You may discover that your 6.4L Powerstroke has a cracked piston after the piston has failed with a distinctive crash. The issue affects the entire 6.4L Powerstroke engine but at different times.

The best way to determine the problem is to unlatch the cap on an oil tank running 6.4L. When there’s a crack in some pistons, the pressure on the crankcase increases and can blow off the cap.

Notice: If you want to investigate this issue, be cautious, as the lid can fly off rapidly. This isn’t a reliable method to determine the cause because normal pressures in the crankcase could create steam from the oil cap in a running vehicle. Bring your car to a specialized repair facility.

Like an old radiator that is damaged, the most effective solution for a damaged 6.4L piston would be to swap it. Maxxforce pistons are joint replacements since they have a lip that is rounded and has additional material that can deal with heat. It is also less prone to cracking.

You’ll also need to paint the pistons to improve their durability and resistance to heat. You can purchase the CERAKOTE Elite Series Oven Cure Ceramic Coating Starter Kits (available on and carry out a DIY preventative measure using an online application guide.

Replace the EGR Coolers.

International upgraded its 6.4L Exhaust Gas Recirculation (EGR) system by adding an EGR Cooler, as the previous 6.0L only had one EGR cooler.

The EGR system decreases the temperature of the combustion chamber by introducing exhaust gases. The lower temperature reduces the formation of nitrous Oxide while preserving the engine’s performance. Hot exhaust gasses pass via EGR coolers to be cooled before they enter the combustion chamber.

Stock EGR coolers are often cracked and release coolant or water in areas where they shouldn’t be.

Detecting a leak in the EGR cooler is possible by observing steam emanating from the exhaust. It means that water has leaked in the exhaust in which hot gasses have evaporated. However, if you see an odor of white smoke emanating from the exhaust system, not steam, check out the article to find the causes and solutions.

If you plan to upgrade your 6.4L Powerstroke’s cooling system, I recommend aftermarket versions because they last longer and increase your engine’s power output.

Install an air-cooling system.

It is important to note that the EGR coolant is usually exposed to extreme temperatures, which can cause breakdown. The heat eventually deteriorates the coolant and the EGR cooler’s pipes. This introduces particles into the system.

They can block the cooler, decreasing its efficiency and impacting the emission control.

This is why it is necessary to install a coolant filtration system such as that of the 6.4L Revive Kit 4 with ARP Studs Head Gaskets Oil Cooler (available on This kit has everything you require to keep the grumpy creatures from your engine’s cooling system.

Install an extra oil cooler.

Sometimes, the issue lies more with the oil cooler than the motor itself. Like the EGR cooler, the coolant in the oil cooler can lead to blockages.

This is why you must know the temperature of the engine’s coolant and Oil. If the difference between them exceeds 14 degrees, your system isn’t cooling it sufficiently fast.

Unfortunately, repairing an oil cooler is impossible once it gets blocked. You’ll need to replace it. Take it off, preferably with a replacement made from aftermarket parts.

To increase durability, you can install an extra oil cooler. It decreases the load on the engine’s oil cooler and improves its capacity for cooling Oil.

The Mishimoto MMOC-F2D-08 Replacement Cooler(available on is a good cooler that works with the 6.4L Powerstroke. A lifetime warranty covers lifetime, but you’ll need professional assistance installing it.

Change the engine Oil Regularly.

You might have heard that a 6.4L Powerstroke’s Oil must be replaced at twice the average rate.

This is due to the vehicle’s emission reduction system, specifically Diesel Particulate Filter (DPF). DPF DPF has been explicitly designed to capture soot, a dangerous combustion product.

One of the major drawbacks of the DPF is the fact that it has a limited capacity to store soot. The soot must be burnt into ash to prevent the DPF from becoming blocked.

In contrast to others (which direct the diesel spray into the exhaust), This 6.4L Powerstroke sprays DPF-cleaning diesel inside the combustion chamber during the exhaust stroke. The diesel is released along with the exhaust gasses.

As you can imagine, any leftover bits of fuel end up along the cylinder wall. These bits end up in the engine oil, affecting its capability to maintain the engine in working condition.

So, you’ll need to replace the Oil in the 6.4L Powerstroke every 4,000-5,000 miles (6,440 to 8,050 km).

This will keep the Oil from becoming too contaminated and introduce clean fluid into your engine, increasing its endurance.

Use the HOAT Coolants

Its 6.4L Powerstroke engine runs very hot, putting extra stress on the coolant. Coolant in the engine absorbs heat from the engine’s components that are sweltering before releasing heat through radiators.

Occasionally, the coolant is so hot that it causes erosion of the engine channels, creating an issue called “coolant cavitation.”

If the erosion continues unchecked, the coolant could create an opening, which allows coolant to leak into the Oil, which can cause the engine to fail catastrophically.

You can stop cavitation in coolant by adding specific additives to the coolant reservoir. The metallic salts shield the engine’s components from rust.

You can also use hybrid organic acid technology (HOAT) coolants. HOAT coolants last longer than traditional coolants and are formulated to protect engines.

For instance, rex G05 Phosphate-Free Concentrate Antifreeze/Coolant1 GA (available on is suitable for gas and diesel engines. It is evident from its name that it will aid in protecting your coolant from freezing in the colder months.

Eliminate the DPF

Most of 6.4L Powerstroke’s reliability issues are due to the measures implemented to lower emissions, including the DPF. Eliminating it will solve several reliability issues; however, doing this could violate federal law.

The Clean Air Act criminalizes the removal of the DPF or altering the vehicle’s design to let exhaust gases override the filter. The amount of fines imposed by the EPA will vary based on the weight of the vehicle and miles traveled, as well as the intention to alter the DPF.

If you use your vehicle exclusively for competitions or off-roading, you can remove the DPF. If you’re unsure whether you can eliminate this component, consult someone more knowledgeable about the legalities involved.


What are the common issues with the 6.4 Powerstroke engine?
Common issues include turbocharger failures, EGR system problems, and fuel system issues.

How can I improve the reliability of my 6.4 Powerstroke engine?
Regular maintenance, installing an aftermarket air intake and exhaust, and using high-quality fuel additives can improve reliability.

What is the best oil to use in a 6.4 Powerstroke engine?
Using a high-quality synthetic diesel engine oil with the correct viscosity rating is recommended for optimal performance and reliability.

Are there any specific coolant recommendations for the 6.4 Powerstroke engine?
Using a reputable ELC (extended life coolant) that meets Ford’s specifications is essential for maintaining the engine’s reliability.

How often should I change the fuel filters on my 6.4 Powerstroke?
It’s recommended to change the primary fuel filter every 10,000-15,000 miles and the secondary fuel filter every 20,000-30,000 miles.

Can tuning or reprogramming the engine control module (ECM) improve reliability?
Yes, custom tuning can optimize performance and efficiency while enhancing overall reliability of the 6.4 Powerstroke engine.

What are some signs that indicate potential reliability issues in my 6.4 Powerstroke engine?
Signs include loss of power, excessive smoke from exhaust, unusual noises, or frequent check engine lights.

Is it worth investing in aftermarket upgrades to make my 6.4 Powerstroke more reliable?
Yes, upgrading critical components such as intercoolers, turbos, and fuel delivery systems can significantly enhance the reliability of your 6.4 Powerstroke engine.


It’s a shame that an engine as powerful as that of the 6.4L Powerstroke has so many problems with its reliability. You can boost the durability of your vehicle by installing a variety of accessories and observing the vehicle more closely than you do with other vehicles.

The adjustments are going to cost you the same amount, but they’ll be less expensive than the damage caused by a lack of reliability. If you need clarification on the root of the issue, contacting an expert is the best option.

Related topic: which 6.4 powerstroke years to avoid

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