The car engine has drastically upgraded over time. These types of diesel engines are used in many places like trucks, ships, trains, etc. there are three top names in the engine market are Powerstroke engine, Duramax diesel engine, Cummins engine and they all work great at each of their places.
Although they have some superficial differences so which brand is the best, it depends on your choice. Knowing the facts about them will make the decision easy to choose.
Cummins Vs PowerStroke Vs Duramax
Before picking one of them, read the article and take a look at these three engines and their specifications.
The Cummins: Differences from Powerstroke & Duramax
To understand the differences between Cummins Vs. PowerStroke Vs. Duramax, we will have to understand the history and features of each engine. Here are the details:
History of Cummins
It is the oldest engine of the 20th century, formed in 1919, and the entrepreneur’s name is Clessie Lyle Cummins. The engine was first created for farm use, and then it was produced for vehicles like ram trucks, busses, Fiat Chrysler’s Ram, and Many other truck makers.
It is an alternative to gasoline engines that has low-down torque, but the fuel economy is right here, which makes it popular. As the day passed, the company upgrades the features. Each of the cylinder heads is 2-valve, made from cast iron, and the fuel injection, turbocharged, is upgraded over time.
Intercooler and injection pump
The first fuel injection did not have the intercooler, but in 1991 they added it to boost the power of the engine. In 1994 the injection pump was replaced by the Bosch P7100.
It can maintain 175 horsepower and 420 lb.-ft. Of torque. In 1998, the P7100 injection pump created 215 horsepower and 420 lb.-ft. Of torque. In 2001, it added an extra ten horsepower.
They also improve the emission requirements like 4-valve-per-cylinder head, fuel injection system, etc. in 2003, they invented a common-rail injection system. The output is more powerful here, and it produces less noise and vibration. In the 2007 model year, the 5.9L Cummins converted into 6.7 liters.
The horsepower is increased in 350 and 650 lb.-ft. of torque. In 2018, they did not upgrade the emission system much, just increase the horsepower at 370 and 800 lb.-ft. of torque.
In 2019, they upgraded 1,000 lb-ft torque and decreased the compression ratio. The turbocharger produces 33 psi of boost, and the engine weight is less than the previous one.
The crankshaft has a 10-bolt crank flange, and the block is made from graphite iron, and the connecting rods, piston bearings are redesigned.
- Cast-iron head material
- Inline-6 configuration
- 16.2:1 compression ratio
- 107 mm x 124 mm Bore and Stroke
- 6.7 L and 408 cubic inches Displacement
- OHV with 4 valves per cylinder Valvetrain
- graphite iron engine block
- 400 horsepower
- 1,000 lb.-ft. torque
- 1-5-3-6-2-4 firing order
- Bosch CP3 common rail high pressure Direct injection Fuel system
- Gray cast iron Block Material
Common Faults of Cummins
Here are the common faults of Cummins engine:
Particulate Filter of Cummins Diesel Get Clogged
The engine has no SCR system, and it operates a rich air-fuel the mixture to keep the NOX lower. So, the clogged diesel particulate filter (PDF) happens much quicker.
Failure of Turbo Charger
The Cummins has a variable geometry turbocharger, so it gets some failure points. Sometimes the moving components of the turbine create excessive turbo lag with the installation to the engine power.
Also, leaking oil is a common problem here.
Fuel dilution is another problem you will face in this engine. The engine releases raw fuel, and it goes to the cylinder in the combustion process. The energy cannot pass much through the cylinder to the crankcase.
The engine can reach high torque, so the cylinder gets excessive pressure which causes head gasket failure.
Power Stroke Diesel Engine
Powerstroke engine is another reputed line for power and heavy-duty vehicles. See their features and details.
History of Powerstroke
This engine brand is an international harvester engine. It is first invented in 1982, named Detroit Diesel V8 engine, which was 6.2L. But Ford upgrades it 6.7L and use it their Ford Super-Duty pickup trucks, ram trucks, and other heavy-duty vehicles.
It is only their first venture, the other Powerstroke engine produced by international Navistar.
First Powerstroke Diesel Engine
Ford’s first power stroke diesel engine produces 175 horsepower, and 318 lb.-ft. of torque at that time. In 1988, the displacement increased to 7.3L.
In 1993, the boosted the horsepower to 215 and torque to 425 lb.-ft. It has a cast-iron block and cylinder heads. In 1999 they added an intercooler and increased 275 horsepower and 525 lb.-ft. of torque.
In 2003, the displacement increased to 6.0L. 7.3L engine still produces that time, but it stopped in 2004. They raised 325 horsepower and 570 lb.-ft. Of torque. Although 6.0L did not like by people because of its so many faults.
Si in 2008, they redesigned the engine in 6.4l and increased 350 horsepower, and 650 lb.-ft. of torque.
But the reliability is not that better. 6.4L uses a high-pressure common-rail fuel system for the first time, but the partnership between Ford and Navistar did not go long. In 2011, they replaced 6.4l to 6.7l.
6.7l Power Stroke
6.7L Power Stroke engine has everything. It is called a scorpion. The reliability and dependability are much better here. In 2011, it had 390 horsepower, and 735 lb.-ft. Of torque. It has a twin turbocharger and a 4-valve-per-cylinder valvetrain.
The graphite iron blocks and aluminum heads show compactness to the engine. In 2018, the upgrade 450 horsepower and 935 lb.-ft. of torque, which is huge.
6.7L PowerStroke Specifications
- 6.7 L and 409 cubic inches displacement
- V-8 Configuration
- 99.1 mm × 108.0 mm Bore and Stroke
- Compacted graphite iron block and aluminum head
- OHV with 4 valves per cylinder Valvetrain
- 16.2:1 Compression ratio
- 450 horsepower and 935 lb.-ft
- Bosch CP4.2 common rail high pressure direct injection fuel system
- 1-3-7-2-6-5-4-8 firing order
- Smart exhaust brake function
Common Issues of Powerstrokes
The early 6.0l power stroke engine had too many issues and faults that people tend to dislike it, so when they upgrade it to 6.7l, most of the problems are gone. But some of them are still you can feel such as
Radiator and Coolant Failure
These two problems were also common in 6.0l. They mount the radiator near to the engine, so the pressure and heats make the radiator failure and create leakage.
Also, coolant leaks most often. The fittings of the coolant are not that good.
EGR System Problem
This is an old problem, and it persists. They cannot solve this problem, so that you will face the EGR cooler clogged sometimes.
It is a common and complicated problem in this engine. Other turbo-related questions can also happen. The bearings are made from ceramic, which creates issues most of the time.
Glow Plug Failure
Glow plugs are a susceptible part and weak point of the engine. Failure of these glow plugs can damage the entire engine but the 6.7l resolve the issue, and you won’t face this problem much.
SCR system issues
This simple device can burn out and make the injector clog up. It has a NOx sensor that can damage at high exhaust temperatures.
Fuel System Failure
Sometimes high-pressure fuel pump can make the fuel system failure. The pump produces debris to the entire fuel system, and you have to replace the fuel pump and other parts.
Duramax Engine: Differences from Powerstrokes & Cummins
To learn the differences of these engines, now we are going to discuss on Duramax.
In 1982, General Motors produced a 5.7L Duramax engine with 120 horsepower and 220 lb.-ft. of torque. Then they update the displacement. 6.2L 130 horsepower and 240 lb.-ft. of torque.
In 1995, the displacement change in the 6.5L Detroit Diesel engine, and they added turbocharger.
First Generation Duramax
In 2001, the first-generation Duramax updated the displacement 6.6L with 300 horsepower and 520 lb.-ft. of torque. You will find these engines in the early years of Chevrolet Colorado, GMC, Chevy Silverado, and other truck models.
This heavy-duty engine has a common-rail Bosch CP3 injection pump, which is different from other engines, 4-valves-per-cylinder is another improvement. The cylinder heads are made from aluminum, which was also reliable.
The Next Generation
In 2004, they updated the engine that calls the LLY engine. They added a variable geometry turbocharger; the emission level is also reduced. In 2006, they upgraded the injection system, redesigned the piston and engine block with 360 horsepower and 650 lb.-ft torque.
In 2007, the engine released their third generation LMM engine of pickup trucks and other vehicles.
They reduce emissions and added several new additions. In 2011, they released the LML engine and added higher-pressure fuel injection with 397 horsepower and 765 lb.-ft. of torque. It is also known for better throttle response along with proper improvement of other units.
In 2017, they upgraded the horsepower 445 and torque to 910 lb.-ft. they called it the L5P Duramax super duty engine, which has more strength and power than others.
It has a high-efficiency air-to-air intercooler, automatic speed feature, better common rail fuel injection, which reduces engine noise better than before.
Specifications of Duramax
- V-8 Configuration
- 6.6 L and 403 cubic inches displacement
- OHV – 32 valve, 4 per cylinder, mechanical roller lifters valvetrain
- 103 mm x 99 mm Bore and Stroke
- Grey iron w/ induction-hardened cylinder walls and aluminum head
- 1-2-7-8-4-5-6-3 firing order
- 16.0:1 compression ratio
- Better throttle response
- Electronically controlled and actuated variable geometry turbocharger
- 445 horsepower and 910 lb.-ft torque.
- Denso Common Rail high-pressure Direct injection fuel system
- Allison 1000 Series 6-speed automatic transmission
Common Issues of Duramax Engines
Like every engine type, Duramax also has issues that needed to be figured out. Here are those:
The coolant pump is not right here. The factory design has some lacking, which is the leading cause of the cooling problem. Overheating problems is another reason here.
The fuel line design is also another problem, and there is no fuel lift pump. Sometimes the high-pressure fuel pump creates a small crack on the fuel filter. The housing is also inadequate. Air can seep in the engine.
The SCR Issue
SCR is a simple device with many weak points. It faces clogging injection, burn out tank heater, damage NOx sensor, and other issues are very common.
The injection parts are sensitive here. If you use poor quality fuel and do not change the fuel filter regularly, the injection system will face a problem.
Crankcase Ventilation System
The design of the crankcase ventilation system is not that good. The intercooler and connecting tubing often face the problem.
Which Diesel Engine is the Most Reliable?
Knowing these three diesel engines, it will be challenging to select the most reliable engine for you. But if you compare the three of them, I would say the most reliable diesel engine is 5.9L Cummins 6.7l. The block and head materials are made of cast iron, which is stronger than others.
Also, the four valves per cylinder have million-mile durability. The fuel economy, high power torque, injection system works excellent, and they could increase horsepower over time.
The faults or problematic issues are also fewer than Duramax and power stroke. It has more luxurious Ram 3500, which is higher than the others.
Because all of these are compared, the cumins have superior popularity. But it depends on your comfort and choice, so knowing which is better, you should try them all and then decide.