Many people are a little uneasy about the 6.4 Powerstroke, the big brother of the 6.0 Powerstroke because we have all heard horror stories about those vehicles. But how awful is the Ford 6.4 Powerstroke diesel?
Similar to the 6.0 version, the engine is a very reliable performer once minor issues have been resolved. We’ll go over some things to check for when buying one and some maintenance advice if you currently have one.
Ford’s 6.4 Powerstroke was only produced for a short time before being phased out a few years later. However, throughout its manufacturing period, this engine was a beast, far outperforming its rivals.
Nevertheless, while being a strong performance, it has certain issues, much like other engines. Ford introduced several year versions of the 6.4 classification engine between 2008 and 2010, some of which were more problematic than others.
You may thus be curious as to which 6.4 Powerstroke years to avoid and why. We’ll go over all you need to know about one specific 6.4 Powerstroke model today, one that you should avoid.
A 6.4 Powerstroke: What Is It?
The first power stroke engine for Ford’s light trucks was the 6.4 Powerstroke, which was pre-equipped with two turbochargers.
Super duty Ford Pickup Truck by Tabercil / CC BY-SA 2.0. Ford’s 6.4 Powerstroke only saw a brief run of production before being phased out a few years later. But this engine was a beast when it was being made, easily exceeding its competitors.
Ford wanted to create a diesel engine that was more ecologically friendly, therefore the 6.4 power stroke was fitted with a new Diesel Particulate Filter (DPF) to lower emissions.
6.4 Power In comparison to its predecessors, Stroke can withstand greater boost levels and create more horsepower and torque.
At the flywheel, this engine produces 350 hp (261 kW) and 650 lb-ft (881 Nm) of horsepower and torque, respectively. A compound VGT turbo system was also used in this power stroke engine for improved throttling.
The 6.4 Powerstroke engine also has an OHV 4-valve system, a DPF, and dual EGR coolers, all of which contribute to lowering exhaust gas temperatures by up to 1,000 degrees and lowering emissions.
Which are the 6.4 Powerstroke Years to Avoid?
There are several 6.4 Powerstroke models to choose from, and practically every year’s model has its advantages and disadvantages.
Ford introduced the 6.4 Powerstroke in 2008 following the catastrophic breakdown of the 6.0 Powerstroke. Before being phased out, the engine operated for the whole two years. There were three variants of the 6.4 Powerstroke. As follows:
- 2008
- 2009
- 2010
The year with the lowest 6.4 Powerstroke rating is 2008. Customers have given this model some negative reviews. It is therefore imperative that you steer clear of this model.
While all three of the 6.4 Powerstroke models experienced some issues, 2008 tops the list for the sheer volume of issues. This is the final Ford Navistar manufactured before Ford severed ties with the two businesses.
The 6.4 Powerstroke has several different problems. Some of them include DPF clogging, problems with the oil cooler and vehicle acceleration, brittle pistons, radiator, up-pipe leaks, etc.
Users have also contacted me about additional problems, such as tainted gasoline, bad mileage, etc. There are also additional issues, which I will go into in more detail later.
Issues with the 2008 Powerstroke
Even though there are various issues, the most frequent steering seizing issue affects the 2008 model. Most customers have claimed that the 2008 models abruptly and silently seize their steering. When the car is moving, this happens.
Accidents on the highway may occur as a result of an abrupt loss of steering control. Therefore, it suffices to avoid the 2008 model for this reason alone.
F-550 4×4 Single Cab Rollback Tow Truck by Dana60Cummins / CC BY-SA 3.0. The 6.4 Powerstroke engine boasts an OHV 4-valve system, a DPF, and dual EGR coolers, all of which help to reduce pollutants and bring exhaust gas temperatures down by up to 1,000 degrees.
Poor mileage is another troublesome concern with the 2008 6.4 Powerstroke. Due to the emissions from diesel filters’ requirement for fuel to renew combustion temperatures throughout combustion events, this is particularly true when there is considerable traffic.
The total fuel mileage will decrease as the number of regeneration cycles increases.
Which Used 6.4 Powerstroke Years are Safe to Buy?
From 2008 to 2010, the 6.4 Powerstroke was produced; the 2008 series was the most troublesome. But it’s wise to get a secondhand 2010 6.4 Powerstroke.
In 2008, the 6.4 Powerstroke V-8 diesel engine was introduced for Super Duty vehicles as a replacement for the 6.0L, which was prone to problems. The 2008 series, however, had some serious faults that were fixed in the 2010 season.
In addition, 2010 6.4 Powerstroke is a better engine than its predecessor and, with the right upgrades, it can perform like a beast.
How Many Miles Can a Well-Maintained Ford 6.4 Powerstroke Engine Go?
Despite a few common problems, the 6.4 Power Stroke should last 250,000 miles or more.
When put through dynamometer testing, it showed a lifetime of 500,000+ miles that was scientifically validated. This is the estimated service length before 10% of all engines need substantial maintenance that requires removing the fluid pan or exhaust manifolds.
The 6.4 L is a very tough vehicle with serviceability that may be increased to 600,000 miles with careful maintenance.
Is the 6.4 Powerstroke Reliable?
The Ford 6.4 Power Stroke turbodiesel’s dependability. It is difficult to talk about this. Some people adore the 6.4 diesel and insist that it is a vast upgrade over the 6.0 Powerstroke. Others claim that the 6.4 is one of the least dependable Ford diesel engines because of their horrible experiences with it. The two things that reality prefers are in between.
It’s not only the 6.4 Power Stroke here. It was produced during a time when emissions equipment was getting increasingly complex. In this essay, we omitted a couple of those issues that may also be regarded as widespread. However, many failures, such as DPF, EGR, oil coolers, etc., are brought on by pollution regulations and the additional equipment needed.
To increase the Ford 6.4 diesel’s dependability, much of this may be eliminated. However, the 6.4 Powerstroke also has a few unrelated problems including radiators, cracked pistons, chafing HPFP wiring, etc.
Another problematic issue with 2008 6.4 Powerstroke is its poor mpg. This is especially true when there is a lot of traffic since emissions from diesel filters require fuel to maintain combustion temperatures during combustion events.
Having stated that, we will comment on the dependability of the 6.4 Power Stroke average. It is unquestionably less dependable than some of the more established legends, such as the 7.3 Power Stroke or 5.9 Cummins. However, with all of the emissions-related issues today, it’s not an accurate comparison.
Which are the Common 6.4 Powerstroke Issues?
Ford trucks only used the 6.4 Power Stroke for a brief period. Additionally, because Ford developed and produced the 6.7 Powerstroke internally, it is the final Ford diesel from International.
Ford 6.4 diesel engines have reliable factory output of 350 horsepower and 650 torque. Good results for the time the 6.4 Powerstroke was introduced. Some people believe that the 6.4 is more reliable than Ford’s earlier 6.0 diesel engine.
No engine is flawless, though, and this isn’t an exception. In this post, we talk about several 6.4 Power Stroke dependability issues that are frequently encountered.
The following are a handful of the 6.4 Power Stroke engine’s most frequent issues:
- Radiator leak issues
- DPF clogging issues
- Up-pipe problems
- Oil cooler issues
- Fuel dilution problems
- Cracked pistons issues
- Acceleration issues
In this piece, we’ll delve further into each of these issues and go through each one in more detail. It’s essential to remember that just because we label these issues prevalent doesn’t mean they necessarily impact a lot of 6.4 diesel engines. Instead, these are a handful of the most prevalent problems. Additionally, failures that aren’t covered in this article can and do occur.
After that, let’s go into the typical 6.4 Powerstroke issues mentioned above. We’ll also provide some concluding remarks on Ford’s 6.4 dependability.
1. Issues with Leaking Radiators
Due to head gasket problems, 6.0 Power Stroke engines occasionally had coolant leaks. However, the radiator is more likely to blame if there is a coolant puddle under the 6.4 Powerstroke.
The radiator’s plastic ends are prone to developing leaks due to cracking or separation. It is without a doubt one of the Ford 6.4 diesel’s most frequent problems.
The 6.4 Power Stroke may quickly start to overheat if too much coolant is lost. To prevent more harm in this situation, it’s critical to promptly turn off the engine.
In any case, a radiator leak has to be addressed immediately. This is especially true if your Ford 6.4 Powerstroke has a serious radiator leak.
F-250 Super Duty XLT Tremor by Jstoker421 / CC BY-SA 4.0. Ford 6.4 diesel engines consistently produce 350 horsepower and 650 torque at the factory. For the time the 6.4 Powerstroke was launched, the results were good. Compared to Ford’s older 6.0 diesel engine, some individuals think the 6.4 is more dependable.
The 6.4 turbodiesels’ visible leak, overheating, and steam coming from the engine bay are signs of a radiator issue.
On the Ford 6.4 engine, a leaky radiator is typically easy to identify. Look under the truck for any observable leaks. If coolant is spilling onto heated components, steam may also come from the engine compartment. Last but not least, if the coolant loss is serious enough, overheating may happen quickly.
We strongly advise replacing the radiator if you plan to retain your 6.4 diesel for an extended period. Radiators made by Mishimoto are a popular alternative for the 6.4 Power Stroke.
They’re not cheap, though, they cost close to $900. You can either choose an aftermarket radiator or the original equipment radiator. Those may cost anywhere from $200 and $500 depending on the radiator.
For the radiator, labor typically takes 2 hours, so budget an extra $200 for that. The total cost of replacing the 6.4 diesel radiator might range from $400 to more than $1,000.
2. Clogging of the Turbodiesel DPF
The 6.4 Powerstroke isn’t an anomaly; diesel particulate filters (DPF) have historically been troublesome components on many contemporary diesel engines.
The Ford 6.4 is the company’s first diesel pickup truck to utilize a DPF. Before they leave the exhaust, particles are supposed to be captured by a DPF. This enhances emissions but also causes problems with filter clogging.
Some elect to remove the DPF because it is a typical issue with the 6.4 Power Stroke. Once the filter is overly clogged, it might result in a variety of problems. DPF blockage puts more strain on the turbo and engine.
This is due to the possibility of significant back pressure from a blocked Ford 6.4 DPF. Hot exhaust gases are consequently difficult for the engine to expel, which can put more strain on various elements.
Power reduction, a long crank, and error messages are a few signs of a clogged DPF on the Ford 6.4 diesel.
The 6.4 Power Stroke will suffer significantly more back pressure when the filter clogs. As a result of the engine’s difficulty to swiftly expel exhaust gases, this frequently causes power loss. Long cranks or fault codes may also be signs that anything is wrong.
There are a few effective fixes for blocked DPFs. Often, the simplest fix is to remove the filter and clean it. That won’t, however, prevent the DPF from possibly clogging once again shortly after.
This is a key factor in the decision of many 6.4 Power Stroke owners to entirely remove the DPF. However, removing the Ford 6.4 DPF can raise issues with the law and emissions testing. Another choice is aftermarket diesel particulate filters, however, these may be rather expensive.
Ford F-550 4WD by Mr.choppers / CC BY-SA 3.0. The Ford 6.4 is the first diesel pickup truck produced by the manufacturer to use a DPF. Particles are meant to be caught by a DPF before they exit the exhaust. This improves emissions but also increases the likelihood of filter clogging issues.
3. Up-Pipe Issue
Another prevalent issue with Ford 6.4 Power Stroke engines is the exhaust up-pipe. The up pipes expansion joints are prone to cracking, especially as they get older and have more use.
Vibration and heat cycles are typically to blame for the problems. A relatively straightforward yet crucial component of the 6.4 Powerstroke exhaust system is up-pipes.
The engine bay may become too sooty when the joints fracture. Also likely to be audible from the engine compartment is a loud hissing sound. We’ll leave it at that because fixing this issue on the 6.4 diesel is rather straightforward.
Hissing from the engine bay, excessive soot in the engine bay and power reduction are common signs of up-pipe issues on the 6.4 Power Stroke.
You will often notice a lot of soot accumulating in the engine area and hear a hissing sound when the joints start to leak and shatter. There might be some power outage as well.
Once the factory-installed pipes wear out, it makes sense to switch to aftermarket pipes. If not, you might have to return there in a few years to remedy the same issue.
For less than $400, you can locate some reliable alternatives for the 6.4 diesel, such as this. Upgrade to up-pipes that won’t encounter the same issues because labor can be a bother.
4. Issue with Oil Coolers
Oil coolers are an issue area owing to blockage, just like the DPF. Sometimes an oil cooler blockage is the true problem and EGR failures are misdiagnosed as such. As its name implies, the 6.4 Powerstroke oil cooler is in charge of cooling the engine oil.
It utilizes coolant to cool the oil, and with time, those passageways could clog up. When this happens, engine oil temperatures may increase more than usual.
Keep an eye on the temps of your coolant and engine oil. Normally, the two should stay within 15 degrees of one another. The oil cooler is likely failing if you find that the temperatures on your 6.4 Power Stroke are fluctuating excessively. Once the oil cooler becomes clogged, there is no way to clear it; thus, a full replacement is typically needed.
Watch out for the following signs that the Ford 6.4 diesel oil cooler may be malfunctioning: Oil overheating and coolant temperature deviation.
As previously stated, the temperature differences between the coolant and oil should not exceed 15 degrees. The 6.4 oil cooler may be too blocked to function properly if the oil is frequently getting too hot.
The cost of the OEM 6.4 Powerstroke oil cooler is $350–500. But if you choose an OEM part, you could have to replace it again in 50,000 to 80,000 miles. They occasionally endure longer, but you must be prepared to take the risk.
Otherwise, Mishimoto charges only $150 for an oil cooler modification. The 6.4 diesel is also covered by a lifetime warranty. We’d probably choose it first.
Ford F-750 Super Duty by N509FZ / CC BY-SA 4.0. Like the DPF, oil coolers are a problem area because of obstruction. Sometimes EGR failures are incorrectly identified as an oil cooler blockage, which is the real issue. The 6.4 Powerstroke oil cooler’s primary function, as suggested by its name, is to cool engine oil.
5. Problems with Fuel Dilution
The procedure that makes an effort to maintain the DPF clean is called active regeneration. This is accomplished by the Ford 6.4 diesel by injecting fuel during the exhaust stroke.
The gasoline may now leave the cylinder and go downstream in the exhaust as a result. This eliminates hazardous emissions and keeps the DPF clean. However, Ford’s approach to creating this system has a fundamental weakness.
For direct fuel injection into the exhaust stream, some engines employ an additional injector. On the exhaust stroke, the 6.4 Power Stroke injects gasoline into the cylinders.
This makes it possible for gasoline to collect in small amounts on the cylinder walls, where it might pollute the engine oil. Oil dilution by gasoline is acceptable and shouldn’t have any negative effects.
However, if there is an excessive mixture of gasoline and oil, the oil’s capacity to adequately cool and lubricate the engine may be compromised. The 6.4 diesel internals can suffer from premature wear and tear as a result of this. Not good for the longevity of the engine.
The 6.4 Power Stroke’s fuel dilution issues have no known symptoms or solutions. Instead, we’ll go through a few strategies for minimizing fuel dilution and lowering the possibility that it’ll cause early wear.
First, limit your idle time since idling causes the cylinders to cool. As a result, there is a higher chance that gasoline will adhere to the cylinder walls and thin the oil. Additionally, it’s a good idea to let the 6.4 diesel engine warm up before putting large weights on it.
Finally, we advise sometimes getting an oil analysis done. You may find out exactly how much gasoline is blending into the oil for a relatively low cost. After that, you may modify your oil change intervals to consider the gasoline dilution.
6. Issues with Cracking Pistons
On the list of 6.4 Power Stroke engine issues, this is one of the least frequent, if not the least frequent. Cracked pistons are deserving of a brief notice because it’s one of the most significant problems.
On vehicles with higher mileage, particularly those north of 200,000 miles, this is most typical. On Ford 6.4 diesel engines with lesser mileage, however, piston problems can and do happen.
6.4 Power Simply said, stroke pistons aren’t very resilient. That doesn’t mean they’re bad, and this issue could have been exaggerated a little bit. However, the cracks often start to appear in the piston’s “fuel bowl.”
Then, they could develop considerably worse and stretch across the piston. If it becomes too bad, you might start losing piston pieces and ruining your engine severely.
Excessive smoke, lack of compression, power loss, and misfires are a few signs that a piston problem may exist.
A leaking radiator on the Ford 6.4 engine is usually simple to see. Inspect the truck’s underside for any obvious leaks. Steam may also emanate from the engine compartment if coolant leaks onto hot components. Not to mention, if the coolant loss is significant enough, overheating might occur soon.
Excessive white smoke might come from the exhaust when the pistons in a 6.4 Power Stroke engine break. If you do a compression test, you could also detect a decrease in compression. If the cylinder isn’t creating sufficient compression, this might then result in power loss and misfires.
Since the 6.4 diesel pistons are an internal component, replacing them is not inexpensive. It will need opening the engine, which makes it an extremely labor-intensive task.
Additionally, there is a bit of a problem with 6.4s with greater mileage. You probably want to keep the truck for a lot longer if you’re going to open up the engine to replace one bad piston. When that happens, it probably makes sense to swap out all six pistons in addition to a few other components while you’re inside.
Naturally, that can increase expenses significantly, especially if you intend to modify a few components in the engine. If you want to maintain the 6.4 Power Stroke operating, you should do these things. If not, a fractured piston might not be worth the money.
7. Accelerating Problems
If your engine has acceleration problems, you will never have a comfortable and smooth driving experience. One of the 2008 6.4 Powerstroke’s most annoying issues is the acceleration issue.
The acceleration system hasn’t changed that much. Some users claim that 2008 smokes as it gains speed. It’s impossible to tolerate the smoke since it’s so awful.
Shutting down is an additional concern with the 2008 acceleration. Some claim that the engine shuts off when accelerating. Even the engine starts whining as the car is going.
Because the engine will continue to irritate you with less acceleration and frequent engine shut-offs, it is recommended to avoid this 6.4 Powerstroke year.
Is the 6.0 Powerstroke Better Than the 6.4 Powerstroke?
In any comparison examination, there are often benefits to both engines when they are placed side by side. But when the 6.0 is up against the 6.4, that is not the case.
The 6.0’s utter failures prompted Ford to change its strategy and release the 6.4. The 6.0 does itself no favors by holding the distinction of being the most unreliable engine of all time.
The Conclusion
Ford only utilized the 6.4 Powerstroke for two years before launching their in-house-built 6.7L Power Stroke. From the factory, the 6.4 diesel engine generates a reliable 350 horsepower and 650 torque.
The figures appear good on paper for the time the engine was launched. The 6.4 was also charged with following up on the 6.0 Power Stroke, which had a very poor reputation.
Unfortunately, neither has the 6.4 Powerstroke, which has a poor reputation. While some people think it’s a huge improvement over the 6.0, others think the 6.4 is just as awful. With all of the stringent emissions regulations, we are living in a different time.
When the pistons in a 6.4 Power Stroke engine fail, there may be an excessive amount of white smoke coming from the exhaust. A reduction in compression may be seen by doing a compression test. Power loss and misfires might occur if the cylinder isn’t producing enough compression.
As a result, a lot of the 6.4 Power Stroke turbodiesel’s issues start with the emissions-related issues. The engine does, however, have a few additional problems that are unrelated to emissions technology.
Having stated that, the 6.4 Power Stroke has mediocre feedback for dependability. Indeed, it’s not as good as the 7.3 PS or 5.9 Cummins, but it’s also from a different time.
Maintain your 6.4 diesel engine properly and update if issues arise. The 6.4 Power Stroke may be made into a lot more dependable engine with the correct improvements, however, they can be a little expensive.
Super duty Ford Pickup Truck by Tabercil / CC BY-SA 2.0
Jim Wicks is the founder of MotorVehicleHQ. With over two decades of experience in the automotive industry and a degree in Automotive Technology, Jim is a certified car expert who has worked in various roles ranging from a mechanic, car dealership manager, to a racing car driver. He has owned more than 20 cars over the past 15 years. Ask him about any vehicle you see on the road and he can tell you the make, model and year. He loves the aesthetics of all things cars, and keeps his vehicles in pristine condition.
In his free time, Jim enjoys getting his hands dirty under the hood of a classic car or taking long drives along the country roads. His favorite car? A 1967 Shelby GT500, a true classic that, according to Jim, “represents the pure essence of American muscle.”