Keeping Pace, Part 3: 650-700hp 5.9L Common-Rail

How To Affordably Make Your ’03-’07 Dodge Run With The Rest Of The Pack

As the 5.9L third-gens continue to age, more and more folks with tighter performance budgets are buying them. But in an era where the words ‘big horsepower’ and ‘daily driver’ go hand-in-hand, you’re going to need more than a 500hp-capable tune to keep up with the Joneses. We’ve seen a boatload of ways to get 700 hp out of the ’03-‘07 Cummins platform over the years, and like many horsepower recipes, there is always more than one way to skin a cat. However, the proper path to 650-700 hp is one that keeps your rods in the block, your coolant from boiling, EGT in check, and your transmission from failing.

Going off on a few tangents as possible, we’ll show you the best path(s) to building a 650 to 700 hp common-rail 5.9L this month. Sure the right injector, CP3, turbo(s), and tuning can get you there quickly, but the correct supporting mods shouldn’t be neglected, either. We’ll go over all of that and more this time, and we’ll also touch on the fact that while the ’04.5-’07 model years often appear to be the preferred model years, the ’03-’04 5.9L’s can be made just as potent. Work or play, the following parts recommendations will help your third-gen keep pace with most street-driven diesel you encounter.

First and foremost, the one caveat in all of this is that you’re starting with a 100-percent healthy engine. It makes zero sense to start modifying an engine with an excessive blow-by or one that’s been exposed to an injector failure that damaged a cylinder. After all, the common-rail 5.9L Cummins is no young pup anymore. Most of these factory rotating assemblies have well over 200,000 miles on them at this point. And not to scare you, but the ’03-’07 5.9L’s do drop valve seats on occasion. However, with all of that said it remains a solid platform to add power.

Specific differences exist between the ’03-’04 5.9L and the ’04.5-’07 versions, and those differences begin with the injectors used. Both the early and late versions utilized Bosch solenoid-style units, but the ’03-’04 injectors were equipped with 8-hole nozzles with a 143-degree spray pattern (left). The ’04.5-’07 versions utilized 5-hole nozzles with a tighter, 124-degree spray pattern.

Predictably, to match their respective injector spray patterns the ’03-’04 (left) and ’04.5-’07 pistons are different. Either version is cast aluminum, but the fuel bowl is noticeably different between an early and late piston. The injector and piston changes that took place midway through the ’04 engine’s production run were emissions-driven—and ’04.5 injectors gained a third injection event (per power stroke), the post-injection event, which was implemented to ensure a more complete occurred burn in-cylinder.

The turbochargers were different between ’03-’04 and ’04.5-’07 engines as well. On early models of the common-rail 5.9L, the HE341CW was on board. The HE341CW was a fixed geometry, journal bearing Holset with a 7-blade 56mm compressor wheel (inducer), a 58mm turbine wheel (exducer) inside a 9cm2 0.65 A/R exhaust housing, and utilized a mechanically actuated internal wastegate. Beginning in ’04.5, the Holset HE351CW was used. It too was a fixed geometry, journal bearing turbo, but sported a 58mm compressor wheel (inducer) and an electronically actuated internal wastegate.

As many of you already know, aftermarket turbo options abound for the ’03-’07 5.9L Cummins. From stock-appearing Holsets with significant upgrades to T3 BorgWarner S300s to T4 S400s and compounds, your options for building boost are virtually limitless. However, the simplest path to 650hp can be had with a stock-appearing (though, as mentioned, significantly upgraded) Holset HE351CW or HE341CW. Fleece Performance Engineering’s Cheetah line of drop-in turbos is the big game in town here (a HE351CW Cheetah is pictured), with its Holset-based units offering a larger (63mm) FMW compressor wheel and turbine wheel (64mm) as well as a larger wastegate actuator. On top of that, it doesn’t require an exhaust manifold change in order to run it.

The next step up in the turbo department is the S300. Options abound here, too, but for many, the conversation starts with whether or not you’re going to run a T3 or T4 exhaust manifold. Industrial Injection has long been the hot spot to get your hands on a well-performing T3 S300, with 62mm, 63mm, and 64mm versions all being capable of getting you into the 650-plus hp range. Those looking to open up exhaust flow with a manifold upgrade and a T4 S300 (namely a 62mm to 66mm unit) will be able to better control EGT while making solid horsepower.

Then there are compounds, were achieving 650 or 700 hp is a walk in the park. Properly sized, an S300 over S400 arrangement on a common-rail 5.9L can offer lightning-quick spool up and instant torque, strong mid-range and top-end power, and extremely safe readings on the pyrometer. If you plan to tow a lot and want to be in this horsepower range, compounds are the best option, hands-down.

A goal of 700 hp is feasible with either an add-a-turbo kit (S400 over stock), (industrial injection) a T3 S300/T6 S400 combo, or a T4 S300/T6 S400 arrangement. However, while leaving the factory Holset HE341CW or HE351CW in place can support this horsepower level, it won’t provide any room for growth in the future. On the other hand, S300/S400 combinations do. For towing, S362 and S363 primary charger options combined with an S475 or S480 have long been solid choices for 700hp tow rigs.

Like turbochargers, there are multiple options on the injector side of the equation as well. Depending on the turbo arrangement, we’ve to see 30-percent injectors—and namely Dynomite Diesel Products’ 90hp units—support 650 to 670 hp on the dyno. We’ve also seen Industrial Injection’s 25-percent and 46-percent injectors do the same in recent years.

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The 45-percent over injectors produced by both Exergy Performance and S&S Diesel Motorsports, two well-known names in common-rail injection, are capable of supporting 700 hp or more. In fact, with the right air in the mix, along with good tuning and an upgraded CP3 (which both companies offer), 45 percent over injectors can easily get you there.

Another sound injector option to boost an ’03-’07 Cummins into 650-to-700 hp territory is the 100hp Bosch Motorsport units. These brand-new, OEM quality injectors were all the rage a decade ago and still get the job done today. SAC style nozzles, the appropriate 143-degree spray angle for early engines and 128-degree spray angle for late engines, and reasonable pricing make them a solid choice for anyone on the hunt for an entry-level, rock-solid reliable performance injector.

Although some stock CP3s can support a mild set of injectors such as 30-percent overs without dropping rail pressure, if you really want to hit your goal a CP3 upgrade should be in order. The popular 10mm CP3 from both Exergy and S&S is a common go-to for a pump that supports as much as 800 hp. With either of the milder injector options we’ve mentioned so far, a 10mm CP3 will support 650 hp to 700 hp without issue.

Increasing the stroke of the CP3’s camshaft to 10mm (from 8.2mm stock), along with select other proprietary changes, provides the increased displacement that makes one of these stroker pumps so beneficial in chasing horsepower. Aside from the popular Exergy and S&S pumps, we’ve seen more than our fair share of the Fleece Performance Engineering PowerFlo 750, another 10mm CP3 which can also support in excess of 750 hp.

For a lot of diesel owners, plans for horsepower often expand over time. If your future goals entail making more than 800 hp, it pays to start with an (ATS Diesel) 12mm CP3 or dual pumps now rather than later. In the long run, you’ll appreciate the fact that you laid the groundwork at the outset, and that you ruled out having to buy another high-dollar CP3. The same goes for injectors. Instead of buying a set that just meets your current horsepower goal, you could invest in larger injectors such as 100-percent over units, which can be detuned now and unleashed later when the supporting mods are in place.

Sealing the deal on a common-rail 5.9L Cummins fuel system is a higher flowing, aftermarket lift pump. The systems from FASS and AirDog remain common thanks to their reliability and all-inclusive, tank-to-engine bolt-on nature. For a goal of 650 to 700 hp, either company’s 165-gph low-pressure fuel supply system will suffice.

Fleece all but revolutionized the aftermarket lift pump game when it released its PowerFlo in-tank units. OEM location, dual OEM-style gerotor pumps, and retention of the factory fuel lines and water-in-fuel sensor made the PowerFlo pump a hit right out of the gate. Then when you factor in its ability to flow 170-gph in a quiet manner, and that it also happens to be less susceptible to freezing and gelling up, unlike the external, chassis-mounted competition, the product all but sells itself.

The ’03-’07 5.9L’s propensity to blow a head gasket is much lower than it is on the 6.7L Cummins, but you’re never going to get away with seeing 50 psi of boost (or more) on stock head bolts for the long-term, especially with a higher mileage engine. The last thing you want to do is lift your head in the midst of pursuing your horsepower goals. For the majority of applications, ARP 2000 material head studs (PN 247-4202) will eliminate that from happening.

For higher boost scenarios, such as when smaller, tow-friendly compounds are being used, ARP’s higher tensile strength, Custom Age 625+ head studs (PN 247-4204) would be a good idea. And for ultimate insurance, it might be wise to go ahead and fire-ring the cylinder head at the same time. The benefit of the latter options allows you to grow your horsepower later on down the road as well when your thirst for additional performance needs to be quenched.

A higher boost is usually accompanied by increased engine speed, which means stiffer valve springs are a great insurance item. Even if engine rpm is kept in check, you’re still likely working with older, weaker valve springs residing in your ’03-’07 5.9L cylinder head, and that means valve creep and reversion are possible. The 90-lb springs available from Haisley Machine are routinely run in mildly-modified 5.9Ls for these reasons.

A second frequently employed valve spring upgrade is the 103-lb springs from Hamilton Cams. Good to 4,500 rpm, they provide plenty of elbow room for valve float should you miss a shift or decide to run your 5.9L upstairs. Improved control over the valvetrain eliminates intake and exhaust valve creep at elevated boost—valve creep being what leads to reversion, where exhaust gases enter the cylinder during the intake stroke, thereby sabotaging your horsepower potential.

Further affordable valvetrain assurance can be had in the form of stronger pushrods. For just $179 from XDP, Hamilton Cams’ extreme-duty pushrods will reinforce the link between the rockers and tappets and won’t bend under the strain of added cylinder pressure. Their 3-piece design features 0.120-inch wall thickness and a 12mm outer diameter, vs. 3/8-inch (9.5mm) of stock.

Ensuring the rearmost cylinders don’t see too much heat can keep coolant pressure from the building, freeze plugs from blowing out, and also keep the antifreeze itself from breaking down. To accomplish this, you’ll find a Fleece coolant bypass kit under the hood of countless Cummins-powered Rams. Its system adds a second thermostat, which works based on temperature and not pressures, to lower coolant temp at the back of the engine and also keep ECT consistent across all cylinders.

You can’t have a conversation about ’03-’07 Dodge Rams and not bring up the 48RE’s inability to hold big horsepower and torque in stock form. But thanks to big-name builders like Firepunk, Randy’s Transmissions, Goerend Transmission, and Sun Coast, proven combinations have been developed to support mild to wild engine setups. While you don’t need a billet stator torque converter at this power level, you will need a triple-disc, billet front cover converter, a billet input shaft, an upgraded flex plate, and a higher pressure valve body.

2006 and 2007 5.9L’s came equipped with the desirable CM849 ECM, and these model year engines are the only versions supported by EFI Live. Having access and adjustability over most engine parameters has allowed calibrators to glean safe, clean power from the ’06-‘07 platform for more than a decade. The job of finding a reputable, proven calibrator with a solid grasp of EFI Live software is up to you, but when combined with the mods we’ve gone over already a custom-tailored file will make making 650-to-700 hp a cinch.

For ’03-’05 trucks, HP Tuners is often the go-to tuning choice, and we’ll note that HP Tuners software and hardware supports all common-rail 5.9L’s (’03-‘07). Yet another option for early common-rail Cummins owners is through the Smarty UDC software offered by MADS Electronics. Again, finding a calibrator well-versed in either of the above platforms is up to you.

There are inevitable horsepower facilitators in any 650-to-700hp build, and one item is a free-flowing turbo-back exhaust. Despite the allure of 5-inch systems or the deeper exhaust note they may provide, a 4-inch diameter system easily suffices for this power level. The question of whether to run a dual, conventional, axle dump or bed stack exit is up to you.

An aftermarket intake elbow isn’t completely necessary in your pursuit of 650-to-700 hp, but it certainly helps remove a known choke point in the 5.9L Cummins’ intake tract. Improved airflow from the intercooler to the head equates to lower EGT, aids spool up, and can even increase peak boost. Such is the case with Banks’ Monster-Ram intake elbow, a piece with a 3.5-inch diameter inlet that’s CNC port-matched to the factory intake grid heater.

Even with an EGT-safe set of compounds matched with 90hp injectors, you’ll still want to keep tabs on EGT, as well as trans temp, boost, ECT, and EOT. Edge Products’ renowned color touch screen Insight monitor, now in its third generation (i.e. the CTS3), allows you to do all of that and more. In addition, you can set alerts for when EGT gets a bit too toasty and also data log parameters to help diagnose any issues.

Keeping tabs on EGT with the Insight CTS3 Edge Products calls for the purchase and installation of Edge’s EAS EGT kit (EAS stands for the expandable accessory system). Various additional EAS sensors can be integrated with the Insight CTS3 to view boost, rail pressure, and any other parameter the ECM doesn’t already monitor.

SOURCES

AirDog
877.421.3187
pureflowairdog.com

ARP
800.826.3045
arp-bolts.com

Banks
800.601.8072
bankspower.com

Dynomite Diesel Products
208.209.3214
dynomitediesel.com

Edge Products
888.360.3343
edgeproducts.com

EFI Live
efilive.com

Exergy Performance
616.551.4330
exergyperformance.com

FASS
636.433.5410
fassride.com

Fleece Performance Engineering
855.839.5040
fleeceperformance.com

Haisley Machine
877.948.3164
haisleymachine.com

Hamilton Cams
512.355.9101
hamiltoncams.com

HP Tuners
hptuners.com

Industrial Injection
800.955.0476
industrialinjection.com

MADS Electronics
madselectronics.com

S&S Diesel Motorsport
ssdiesel.com

Xtreme Diesel Performance
888.343.7354
xtremediesel.com

FREQUENTLY ASKED QUESTIONS

How does vehicle maintenance affect the longevity of diesel trucks?

How Vehicle Maintenance Extends the Longevity of Diesel Trucks

Maintaining diesel trucks is crucial to their longevity. Regular upkeep ensures these vehicles perform efficiently and last for several hundred thousand miles or more.

Many diesel trucks reach impressive mileages—450,000, 600,000, even 800,000 miles—when they are consistently and properly maintained. This isn’t by chance; it’s the result of diligent care and attention.

Key Maintenance Tasks

Regular Oil Changes: Fresh oil keeps the engine lubricated, reduces wear, and prevents overheating.
Filter Replacements: Regularly replacing fuel, air, and oil filters ensures impurities do not damage engine components.
Brake Inspections: Regular brake maintenance is vital for safety and preventing more costly repairs down the line.
Tire Care: Keeping tires inflated and aligned helps avoid unnecessary strain on the vehicle and improves fuel efficiency.
Cooling System Checks: Ensuring that the coolant is topped up and free of contaminants prevents engine overheating.

The Impact of Proactive Maintenance

Diesel trucks are built to withstand intense usage, but proactive maintenance is key to realizing their full potential. Trucks that have been well cared for through routine checkups and repairs demonstrate remarkable durability. These vehicles wouldn’t reach such high mileages without the benefits of regular upkeep.

Investing in regular maintenance ensures your diesel truck not only reaches impressive distances but also retains its performance and reliability through the years.

What is the average cost to modify a diesel truck to produce 500 horsepower and maintain that power reliably?

What is the Average Cost to Modify a Diesel Truck to Produce 500 Horsepower Reliably?

Achieving a reliable 500 horsepower in a diesel truck involves a series of modifications that can vary in cost, primarily depending on the components chosen and the specific requirements of your truck’s transmission. Below is a detailed overview of the potential expenses you could expect:

Essential Modifications

Turbocharger Upgrade
Upgrading to a larger or more efficient turbocharger is crucial for reaching 500 horsepower. Costs for turbochargers can range from $1,000 to $3,500, depending on the technology and brand.
Fuel System Enhancements
To support increased power, modifications to the fuel system are necessary. This typically includes high-performance injectors and upgraded fuel pumps. Budget around $1,500 to $3,000 for these changes.
Exhaust System
A high-flow exhaust system will help manage the increased output. Expect to spend between $500 and $1,500.
ECU Tuning
Custom ECU tuning ensures that all modifications work seamlessly together. Professional tuning services generally range from $500 to $1,000.
Intercooler
An upgraded intercooler is often required to keep temperatures under control. Costs are usually between $800 and $1,500.

Transmission Considerations

The specific type and condition of your truck’s transmission can significantly impact the overall cost. Manual transmissions might require less immediate modification compared to automatics, but ensuring reliability might still involve:

Heavy-Duty Clutch or Torque Converter
For manual gearboxes, a heavy-duty clutch is often essential, typically costing $500 to $1,200. For automatics, a performance torque converter might be necessary, priced at about the same range.
Transmission Build or Upgrade
Depending on the power capacity of your existing transmission, a full rebuild or upgrade may be required, which can range from $3,000 to $5,000.

Additional Enhancements

Gauges and Monitoring Systems
To ensure everything runs smoothly, integrating additional gauges (like EGT and boost gauges) can be valuable. This would add approximately $200 to $400.

In summary, modifying a diesel truck to achieve and sustain 500 horsepower reliably involves comprehensive upgrades. Considering all factors, you should budget between $7,500 and $15,000, factoring in both parts and labor. The range can vary significantly based on personal choice, the truck’s starting setup, and the intended scope of work. Consider discussing your project with a professional to ensure all modifications align with your specific goals and needs.

How do high mileage trucks compare in reliability and value to newer, more expensive models?

When comparing high-mileage trucks to newer, more expensive models, several factors come into play regarding reliability and value. High-mileage trucks are often lauded for their durability. Many vehicles achieve impressive mileage marks—sometimes reaching 450,000 miles or more—demonstrating their long-lasting performance if they’ve been diligently maintained. This longevity isn’t coincidental; rather, it’s a testament to both the quality of the engineering and the commitment of their owners to regular maintenance.

Reliability: A well-maintained older truck can have significant staying power. These vehicles are often simpler in technology than newer models, meaning there are fewer electronic components that might fail. Their mechanical nature allows for straightforward repairs, meaning they can continue to operate successfully for years. Regular upkeep, such as timely oil changes and part replacements, is key to sustaining this reliability.

Value: From a financial perspective, high-mileage trucks offer considerable value. They come with a lower price tag compared to new models, making them an attractive option for those seeking dependable transportation without breaking the bank. This affordability, coupled with their proven track record, makes them a savvy choice for many buyers.

In contrast, newer, more expensive models boast state-of-the-art technology and advanced safety features. While they offer modern conveniences and peace of mind with warranty coverage, they also depreciate quickly, losing value as soon as they leave the dealership. Additionally, the complexity of new technology can lead to costly repairs once the warranty period expires.

Final Consideration: Choosing between a high-mileage truck and a new model ultimately depends on individual priorities. If cost savings and simplicity are paramount, a well-maintained older truck is a practical option. However, if modern features and long-term warranty aids in better peace of mind, investing in a new model may appeal more.

What impact do electrical accessories have on the reliability of older diesel trucks?

The Role of Electrical Accessories in the Reliability of Older Diesel Trucks

Electrical accessories can significantly affect the reliability of older diesel trucks. As these vehicles age, issues with electrical components often become more prominent, impacting overall performance and dependability.

Common Electrical Issues

Older diesel trucks frequently encounter problems with their electrical systems. These can include:

Unpredictable Instruments: Dashboard instruments, like the tachometer, may start malfunctioning, leading to incorrect readings.
Faulty Connections: Over time, soldered connections can deteriorate, requiring maintenance to restore functionality.
Malfunctioning Accessories: Electric mirrors and window switches may fail, often needing replacement or repair. While a window switch might work through one control, it might fail when using another, indicating a localized problem.

Maintaining Reliability

Despite these issues, many older diesel trucks boast engines capable of long-term performance. Regular maintenance of electrical components is key to ensuring the rest of the vehicle remains reliable. With diligence in attending to these electrical quirks, owners can enjoy the enduring robustness of their diesel engines while mitigating nagging accessory failures.

In summary, while the engines in older diesel trucks often remain robust and reliable, aging electrical accessories require ongoing attention to maintain overall dependability. Addressing these challenges head-on can extend the life and functionality of the truck.

Is a manual transmission a better option than an automatic for longevity and performance in diesel trucks?

Manual vs. Automatic Transmission: Longevity and Performance in Diesel Trucks

When considering diesel trucks, especially regarding longevity and performance, the choice between a manual or automatic transmission can be crucial.

Advantages of Manual Transmissions

Durability: Manuals are often lauded for their robust construction. With fewer components than automatics, they typically experience less wear and tear over time, contributing to their long lifespan.
Driver Control: Manuals give the driver more control over the vehicle’s power and fuel efficiency. This can be particularly advantageous in demanding driving conditions or when towing heavy loads.
Lower Maintenance Costs: Repairing or replacing parts in a manual transmission tends to be less costly compared to an automatic, due to the simpler mechanics involved.

Advantages of Automatic Transmissions

Ease of Use: Automatics are easier and more convenient, especially in stop-and-go traffic, reducing driver fatigue.
Advanced Technology: Modern automatics come equipped with sophisticated features such as adaptive learning and shift timing which can enhance performance and fuel efficiency.

Longevity Considerations

Maintenance is Key: Regardless of the choice between manual and automatic, the longevity of a truck greatly depends on regular maintenance. Well-maintained vehicles often exceed hundreds of thousands of miles without major issues.
Driving Habits: A careful driving style can extend the life of any transmission type.

In conclusion, while manual transmissions may offer advantages in terms of durability and cost-effectiveness, the best choice ultimately depends on individual preferences and specific needs. Both types have their respective strengths that can cater to different driving styles and purposes.

How do the bodies of diesel trucks with a common rail system hold up over time?

How Well Do Diesel Truck Bodies with Common Rail Systems Last Over Time?

When it comes to the durability of diesel truck bodies with common rail systems, experiences tend to be positive, though with some important caveats.

Common Trouble Spots

Fender Wells: These areas are prone to rust, a common issue many owners report.
Rockers: Similar to fender wells, rockers can suffer from rust, particularly if they aren’t properly maintained.

Factors Affecting Longevity

Location: The environment plays a significant role. Trucks in areas with harsh weather can experience more wear.
Maintenance: Regular care can substantially prolong the life of your truck’s body.

Maintenance Tips for Longevity

To prevent rust and other issues:

Seasonal Cleaning: Dedicate a day in the spring to thoroughly clean the inside of the fender wells and rockers. This can significantly reduce rust.
Protective Measures: Applying rust-proof coatings or other protective treatments can be invaluable.

In summary, while there are areas that may require attention, the overall endurance of these truck bodies is commendable, given regular and attentive maintenance. Ensure proper care and location consideration to keep your truck’s body in good shape over the years.

What is the usual miles per gallon (mpg) for a diesel truck that is used as a daily driver and tow rig?

When using a diesel truck as your daily driver and for towing tasks, you can generally expect different fuel efficiency figures depending on the usage. For everyday driving, diesel trucks typically achieve between 16 to 18 miles per gallon (mpg). However, when these trucks are tasked with towing, the fuel economy usually drops to around 10 to 12 mpg, influenced by the weight being towed.

Keep in mind, these figures can vary based on specific truck models, driving conditions, and personal driving habits.

How does location and maintenance affect the rust and durability of truck bodies?

How Location and Maintenance Impact Truck Body Rust and Durability

The durability of truck bodies, particularly regarding rust, largely depends on two critical factors: location and maintenance.

Location Matters

Where you live plays a significant role in how well your truck’s body withstands the test of time. Areas with harsh winters, where roads are frequently salted, can accelerate rusting. Humid regions also pose a threat, as constant moisture can wear down the metal over time. Conversely, trucks in dryer climates tend to have fewer rust issues simply due to less exposure to moisture and corrosive road treatments.

The Power of Proper Maintenance

Maintenance is paramount in preserving the truck’s body. Regularly washing your truck, especially focusing on areas like the rocker panels and fender wells, is essential. This practice helps remove salt, dirt, and moisture that can lead to rust. Spending a day in the spring thoroughly cleaning and inspecting these areas can significantly prolong the truck’s lifespan. In essence, the more diligently you care for your truck, the more likely it is to remain rust-free and durable.

By ensuring your truck is maintained well and considering where it’s primarily used, you can greatly influence its longevity and resistance to rust.

How does engine longevity compare to the lifespan of the truck chassis in Cummins-powered vehicles?

When evaluating the durability of Cummins-powered trucks, a clear difference emerges between engine longevity and chassis lifespan. Generally, Cummins engines are engineered for long-lasting performance, built to endure for years, often outlasting the very frames they power.

In regular driving conditions:

Engine: Designed for durability, these engines are capable of high mileage and extended service life. Many owners can attest to their engines running reliably well beyond the initial expectations set by traditional automotive standards.
Chassis: Conversely, the truck chassis often face wear and tear more quickly, particularly in vehicles subjected to heavy-duty tasks. Components like suspension, body panels, and other structural elements may require repairs or replacements before the engine shows signs of fatigue.

For trucks involved in rigorous workloads:

The strain on the chassis can be substantial, leading to a reduced lifespan compared to the more robust engines. This discrepancy indicates why many trucks find their engines swapped into new frames over time.

In essence, while exceptions exist, manufacturers widely operate under the notion that owners might trade or sell the truck before any significant structural issues arise. Engines built by third-party brands like Cummins have gained a reputation for endurance, whereas truck chassis may not consistently match that level of durability.

What are the issues with fuel filtration and injectors in common rail diesel trucks?

Sealing the deal on a common-rail 5.9L Cummins fuel system is a higher flowing, aftermarket lift pump. However, understanding the underlying issues is crucial for anyone looking to enhance performance and reliability.

The Challenges

Fuel filtration in common rail diesel trucks is marginal at best. This inadequacy leaves injectors, which are notoriously finicky and susceptible to any and all contaminants, vulnerable. Given that these injectors are also very expensive, even minor contamination can lead to costly repairs.

The Solution

The systems from FASS and AirDog remain common thanks to their reliability and all-inclusive, tank-to-engine bolt-on nature. For a goal of 650 to 700 hp, either company’s 165-gph low-pressure fuel supply system will suffice. These solutions effectively tackle the filtration inadequacies by providing a more robust and reliable flow of clean fuel to the engine.

Fleece all but revolutionized the aftermarket lift pump game when it released its PowerFlo in-tank units. OEM location, dual OEM-style gerotor pumps, and retention of the factory fuel lines and water-in-fuel sensor made the PowerFlo pump a hit right out of the gate. Then when you factor in its ability to flow 170-gph in a quiet manner, and that it also happens to be less susceptible to freezing and gelling up, unlike the external, chassis-mounted competition, the product all but sells itself.

By addressing both the filtration issues and enhancing the fuel delivery system, these aftermarket solutions not only mitigate the risks associated with injector contamination but also unlock the potential for increased horsepower and engine performance.

What are the cost implications of injector issues?

Injectors are quite costly, so any malfunction or damage due to contaminants can lead to significant repair expenses.

How susceptible are the injectors to contaminants?

Injectors are highly vulnerable to contaminants, making them prone to issues when exposed to impurities.

How effective is the fuel filtration system in common rail diesel trucks?

The fuel filtration system is not highly effective, offering only minimal protection against impurities.

What are the pros and cons of diesel trucks equipped with a common rail system?

“First and foremost, the one caveat in all of this is that you’re starting with a 100-percent healthy engine. It makes zero sense to start modifying an engine with excessive blow-by or one that’s been exposed to an injector failure that damaged a cylinder. After all, the common-rail 5.9L Cummins is no young pup anymore. Most of these factory rotating assemblies have well over 200,000 miles on them at this point. And not to scare you, but the ’03-’07 5.9L’s do drop valve seats on occasion. However, with all of that said, it remains a solid platform to add power.

Pros of Diesel Trucks with a Common Rail System:

Engine Longevity: These engines are renowned for their durability and can withstand high mileage with proper maintenance.
Horsepower & Torque: Known for impressive performance, these engines deliver substantial power and pulling capabilities.
Robust Construction: The bottom end and head are exceptionally strong, reducing the risk of significant internal failures.
Fuel System Reliability: No need to bleed fuel lines after major work or running out of fuel, adding to ease of use.
Superior Cooling System: The cooling system is more than capable of meeting the engine’s demands, ensuring efficient operation.
Fuel Economy & Reputation: These engines are celebrated for outstanding fuel economy and a reputation for reliability. Plus, parts availability is excellent, whether stock or performance.

Cons to Consider:

Transmission Mating Issues: There can be challenges in ensuring a seamless connection between the engine and transmission.
Truck Durability: While the engine may last, the truck itself might not match the engine’s longevity.
Fuel Filtration & Injector Sensitivity: The fuel filtration system is marginal, and injectors can be sensitive to contaminants, leading to expensive repairs.
Front End & U-Joint Concerns: The front end may struggle under the weight, and there are many U-joint and drive line length combinations, complicating maintenance.

In summary, while the common-rail 5.9L Cummins engine offers a strong foundation for power enhancements, it’s essential to balance modifications with a clear understanding of both its strengths and potential weaknesses.”

What considerations should be made when purchasing a high-mileage diesel truck?

First and foremost, the one caveat in all of this is that you’re starting with a 100-percent healthy engine. It makes zero sense to start modifying an engine with excessive blow-by or one that’s been exposed to an injector failure that damaged a cylinder. After all, the common-rail 5.9L Cummins is no young pup anymore. Most of these factory rotating assemblies have well over 200,000 miles on them at this point. And not to scare you, but the ’03-’07 5.9L’s do drop valve seats on occasion. However, with all of that said, it remains a solid platform to add power.

When considering the purchase of a high-mileage diesel truck, there are several key factors to keep in mind:

Vehicle Longevity: The durability of diesel trucks hinges on consistent maintenance. A well-cared-for truck can serve you for many more miles, but neglect can lead to costly repairs.
Fuel Efficiency: Keep an eye on your driving habits, as MPG is closely tied to your right foot. While averages might hover around 17 MPG, gentle driving can yield better results.
Transmission Capacity: The stock transmission can typically handle standard power levels. However, if you’re aiming for high horsepower, such as 500hp, transmission upgrades or a full rebuild will likely be necessary.
Potential Engine Issues: Be aware of potential issues with high-mileage engines, like the occasional dropping of valve seats, which can affect performance and reliability.

By balancing these factors, you can make an informed decision that ensures your high-mileage diesel truck is both a reliable workhorse and a powerful performer.

What modifications are necessary for achieving higher power levels?

To reach 500 horsepower, you will need to upgrade the transmission, possibly involving a complete rebuild to handle the increased power.

What are the performance capabilities of the transmission in a high-mileage diesel truck?

The transmission is capable of handling the power levels of a stock engine without requiring modifications.

What is the expected fuel efficiency of a high-mileage diesel truck?

Fuel efficiency largely depends on driving habits. While an average of 17 miles per gallon is common, more efficient driving can yield better results.

How well do the bodies of high-mileage diesel trucks hold up?

With proper maintenance, the bodies of these trucks can remain in good condition, much like any other vehicle.

Is the 48RE automatic transmission an improvement over its older versions in Dodge trucks with Cummins engines?

When discussing the evolution of Dodge trucks with Cummins engines, particularly the ’03-’07 models, the 48RE automatic transmission often becomes a focal point. Yes, the 48RE is a definitive improvement over its predecessors, addressing several issues that plagued earlier models. While not perfect, it offers a solid foundation that can be enhanced for longevity and performance.

You can’t have a conversation about these Dodge Rams without acknowledging the 48RE’s limitations in holding big horsepower and torque in stock form. However, thanks to big-name builders like Firepunk, Randy’s Transmissions, Goerend Transmission, and Sun Coast, proven combinations have been developed to support mild to wild engine setups.

To optimize the 48RE, consider these upgrades:

Triple-disc, billet front cover converter
Billet input shaft
Upgraded flex plate
Higher pressure valve body

While you don’t need a billet stator torque converter at this power level, these enhancements are crucial for those pushing their trucks beyond stock capabilities.

For those who prefer a different approach, considering a manual transmission could be a viable option. This alternative offers a different kind of reliability and performance characteristic that some drivers find preferable.

In essence, the 48RE represents a step forward, with the potential for customization that suits both moderate and extreme performance needs.

Are there alternative transmission options?

Yes, opting for a manual transmission is a viable alternative to the 48RE, depending on personal preference and needs.

Can the 48RE be built to last?

While not perfect, the 48RE can be upgraded and modified to enhance its longevity and reliability.

Is the 48RE an improvement over previous automatic transmissions?

Yes, the 48RE offers enhancements compared to earlier automatic transmissions, marking a step forward in design and functionality.